The disclosure discloses a method of preparing electric and temperature dual-control bi-stable color-changing dyes and microcapsules, belonging to the technical fields of fine chemicals and materials science. According to the disclosure, after an electrolyte, a leuco dye and an organic solid material are mixed according to 1:(2-10):(15-50), a series of electric and temperature dual-control bi-stable color-changing dye compounds having a color change temperature range of −5° C. to +80° C. can be prepared. The dye compounds change color under cooperative control of electricity and temperature, and can be continuously stable at a certain color change state according to different conditions, and finally achieve controllable color change conditions and controllable color change stable states. When being driven by voltage and temperature, the dual-control bi-stable color-changing microcapsules prepared according to the disclosure achieve controllable color change performance and color change stable states, and have the driving voltage being lower than 10 V (much lower than the human body safety voltage 36 V).

Provided herein are color charts and water color pigment solutions useful, for example, in the calibration of reflectance-based diagnostic analyzers.

The purpose of the present invention is to provide: a high-performance polarizing plate which functions for light in an infrared wavelength range; and a liquid-crystal display device or the like comprising the same. Provided is a polarizing plate for an infrared range, which is a stretched film containing a dye exhibiting absorption in an infrared range, the film exhibiting dichroism.

Aqueous leucoindigo solution comprising an aromatic amine, in particular aniline or aniline and N-methylaniline, wherein the concentration of the aromatic amine is below 200 ppm, wherein the leucoindigo salt in the solution is in the form of a mixed sodium and potassium salt, wherein the molar ratio of sodium to potassium is in the range of from above 3:1 to 10:1, preferably wherein the concentration of the salt is in the range of from above 25 to 45% by weight, based on the total weight of the solution.

The invention provides a dyeing solution for lithographic printing plates and a dyeing method for waterless lithographic printing plates that show stable plate inspection characteristics with little decrease in dye concentration and less dyeing unevenness even when used for bulk plate processing. The dyeing method for waterless lithographic printing plates is designed so that when used to dye an image area formed on a waterless lithographic printing plate with a dyeing solution containing an organic solvent, the relation of |β−α|<5 (cal/cm.sup.3).sup.1/2 is held wherein β is the SP value of the polymer compound included in the image area and α is the SP value of the organic solvent. The dyeing solution for lithographic printing plates contains (a) a dye, (b) a specific anionic surface active agent, and (c) an organic solvent containing at least one selected from ethers and alcohols.

Color conversion films for a LCD (liquid crystal display) having RGB (red, green, blue) color filters, as well as such displays, formulations, precursors and methods are provided, which improve display performances with respect to color gamut, energy efficiency, materials and costs. The color conversion films absorb backlight illumination and convert the energy to green and/or red emission at high efficiency, specified wavelength ranges and narrow emission peaks. Film integration and display configurations further enhance the display performance with color conversion films utilizing various color conversion elements and possibly patterned and/or integrated with a crosstalk blocking matrix. For example, color conversion and/or assistant dyes may be used to enhance spectral regions transmitted through the color filters and shape the illumination spectrum, to improve efficiency and performance.

Stable aqueous leucoindigo solution comprising an aromatic amine in the form of aniline or aniline and N-methylaniline, wherein said leucoindigo is in the form of an alkali metal salt; wherein the concentration of the aromatic amine is below 40 ppm determined according to ISO 14362-1:2017(E); and wherein the concentration of the leucoindigo salt is in a concentration range of from 10 to 45% by weight based on the total weight of the solution, and wherein the stability of the solution is measured at a temperature of 23° C.; or wherein the concentration of the leucoindigo salt is in a concentration range of from 45 to 65% by weight based on the total weight of the solution, and wherein the stability of the solution is measured at a temperature of 60° C.

Provided herein are clear aqueous colonoscopy irrigation compositions, and methods for visualization of colonic mucosa during colonoscopy procedure. The composition comprises indigo, blue or green colored contrast dye, polydimethylsiloxane, and muscle relaxant.

Edible colorant compositions containing a monoacylated anthocyanin of Compound I and methods of use are provided. The colorant compositions include at least the monoacylated anthocyanin colorant of Compound I extracted from red cabbage and a metal ion, and have a pH from about 6.0 to about 8.0. The colorant compositions can be derived from a non-artificial product and provide a stable, blue colorant that can be used in food products. Specifically, the monoacylated anthocyanin colorant provides color characteristics similar to those provided by the artificial blue colorant, FD&C Blue No. 1.

Described herein are compositions, optical elements, and methods for improving color discernment. Disclosed is a composition comprising: a luminescent compound; and a light absorbing dye. The luminescent compound is preferably rhodamine B: (I). The light absorbing dye is preferably the porphyrin derivative below: (II).

##STR00001##