An ink composition including a mixed solvent including a first solvent and a second solvent, and a light emitting material, wherein the first solvent and the second solvent each have a vapor pressure of about 1×10.sup.−4 or greater and a boiling point of about 270° C. or less. The ink composition according to an embodiment may be applied to forming an emission layer of a light emitting diode to provide a light emitting diode having increased efficiency.

A method of inkjet printing a gradient dielectric element in a deposition and photo-polymerization process. The method comprises: providing a plurality of complex-dielectric-inks that are inkjet printable including a nanocomposite-ink with an organic-matrix and a nanoparticle filler dispersed within. The plurality of complex-dielectric-inks have a first complex-dielectric-ink having a first photoinitiator and a second complex-dielectric-ink with a second photoinitiator. The first and second complex-dielectric-ink have different wavelength selective photo-polymerization absorption bands such that spectrally discrete exposure results in different degrees of polymerization of the first and second complex-dielectric-ink. The method further comprises providing an optical source to polymerize the complex-dielectric-inks, depositing droplets of the plurality of complex-dielectric-ink and curing the plurality of complex-dielectric-inks, wherein deposition of the plurality of layers result in a volumetric nanoparticle concentration gradient.

A method of inkjet printing a gradient dielectric element in a deposition and photo-polymerization process. The method comprises: providing a plurality of complex-dielectric-inks that are inkjet printable including a nanocomposite-ink with an organic-matrix and a nanoparticle filler dispersed within. The plurality of complex-dielectric-inks have a first complex-dielectric-ink having a first photoinitiator and a second complex-dielectric-ink with a second photoinitiator. The first and second complex-dielectric-ink have different wavelength selective photo-polymerization absorption bands such that spectrally discrete exposure results in different degrees of polymerization of the first and second complex-dielectric-ink. The method further comprises providing an optical source to polymerize the complex-dielectric-inks, depositing droplets of the plurality of complex-dielectric-ink and curing the plurality of complex-dielectric-inks, wherein deposition of the plurality of layers result in a volumetric nanoparticle concentration gradient.

Provided is a thermochromic writing instrument, including thermochromic ink; and a friction unit configured to cause handwriting in the thermochromic ink to undergo a thermochromic change by frictional heat. The thermochromic ink includes a metallic luster pigment added thereto. The thermochromic writing instrument is provided with an attachment hole to attach the friction unit. The friction unit includes an attachment portion to be inserted into the attachment hole and a friction portion in a convex curved surface shape projecting from the attachment hole. The friction portion has a volume Ve and the metallic luster pigment has a volume Vp, the volume Ve and the volume Vp satisfying 5 □ Ve/Vp □ 35, the friction portion 32 has a maximum outer diameter D and a projection length L, the diameter D and the length L satisfying 0.1 □ L/D □ 1.5, and a material for the friction unit 3 has a value of Shore A hardness in accordance with JIS K 7215 of Japan Industrial Standard measured immediately after starting contact with an indenter in a range of 60 or more and 85 or less and has a value (ΔHS) of the Shore A hardness defined by a following equation of 0 or more and less than 5, ΔHS=(Shore A Hardness Value immediately after Starting Contact with Indenter)−(Shore A Hardness Value 15 seconds after Starting Contact with Indenter).

A display apparatus is provided to include: a first substrate on which a light-emitting device emitting light is located; and a main pixel including a first quantum dot layer; a sub-pixel including a second quantum dot layer, the main pixel and the sub-pixel corresponding to the light-emitting device and being located above the first substrate, wherein the main pixel and the sub-pixel are defined by banks, the main pixel changes a color of the light emitted by the light-emitting device, and the sub-pixel transmits the light emitted by the light-emitting device.

Methods for product authentication, which include: providing an article having a substrate with an analyte encoded composition; obtaining a sample of the composition; applying the sample to a test device to obtain test results, analyzing test results from the test device using an electronic device communicatively connected to an authentication authority, wherein the electronic device transmits the test device code and the test results to the authentication authority and confirms or denies authentication after comparison to an authentication database of authentic test results.

Provided are an inkjet printing device, a method for printing bipolar elements, and a method for manufacturing a display device. The inkjet printing device includes an inkjet head disposed above a stage and including a plurality of nozzles through which ink including bipolar elements each having areas doped with partially different polarities is discharged; an actuator disposed in the inkjet head and adjusting an amount of droplet of the ink discharged through the plurality of nozzles; and at least one sensing part disposed in the inkjet head and measuring a number of bipolar elements discharged through the plurality of nozzles.

Provided are an ink set and a printed article, the ink set comprising an ink jet ink A which contains a polymerizable compound, a photopolymerization initiator, and perylene black and in which a proportion of a polyfunctional polymerizable monomer in the contained polymerizable compound is 60% by mass or more, and an ink jet ink B which contains a polymerizable compound, a photopolymerization initiator, and an infrared absorbing dye and in which a proportion of a polyfunctional polymerizable monomer in the contained polymerizable compound is 60% by mass or more.

A recording method is for performing recording by ejecting, onto a recording medium, ink and a reaction solution including a flocculating agent that flocculates a substance contained in the ink, and the recording method includes ejecting the reaction solution as a droplet onto the recording medium, and ejecting the ink as a droplet onto the recording medium. A relationship of Op1≥Op2 is satisfied when an ejection amount of the reaction solution during ejecting the reaction solution in a first recording mode is indicated with Op1, and an ejection amount of the reaction solution during ejecting the reaction solution in a second recording mode is indicated with Op2, the second recording mode having a recording speed lower than the first recording mode.

A recording method is for performing recording by ejecting, onto a recording medium, ink and a reaction solution including a flocculating agent that flocculates a substance contained in the ink, and the recording method includes ejecting the reaction solution as a droplet onto the recording medium, and ejecting the ink as a droplet onto the recording medium. A relationship of Op1≥Op2 is satisfied when an ejection amount of the reaction solution during ejecting the reaction solution in a first recording mode is indicated with Op1, and an ejection amount of the reaction solution during ejecting the reaction solution in a second recording mode is indicated with Op2, the second recording mode having a recording speed lower than the first recording mode.