An aqueous ink jet ink composition is for use in an ink jet recording method. The method includes ejecting ink from an ink jet head including nozzles. The nozzles are configured such that a shape of a side wall surface is a scalloped shape in which a scallop width S1 and a notch depth S2 satisfy S1/S2≥4. The aqueous ink jet ink composition includes a pigment and a solvent that contains a specific compound.

A system and method for applying patterns to surfaces. A pattern may be applied to a surface of an object using a three-dimensional (3D) printer system. The 3D printer system may include a printer head including an applicator holding material used to form the pattern on the surface, a structure configured to hold a substrate to which the material will be applied, and a controller for adjusting a location of the printer head relative to a surface and initiating applying material from the applicator onto the surface. The applicator may be a syringe with a needle. 3D coordinates at which material is to be applied to a surface to form the pattern may be determined and identified based on a relative location of the substrate and the pattern. The pattern may be a speckle dot pattern used in Digital Image Correlation (DIC) material testing and characterization techniques.

An electrospray printing system that produces conformal films includes a printhead. A housing of the printhead includes a solution reservoir operable to receive a solution that includes a print material suspended in a solvent. An electrical potential is applied to the solution to produce an electrically charged solution that is emitted from the solution reservoir towards a target substrate. Electrostatic focusing is used to guide the print material to the target substrate.

A water-based ink includes a pigment, and water, in which a viscosity at 20° C. is in a range of 2 mPa.Math.s to 7 mPa.Math.s, and a yield value at 20° C. is less than 0.2 mPa, and the yield value at 20° C. when evaporating 25% of the water is less than 0.8 mPa.

There is provided a liquid discharge head including: a channel unit; a piezoelectric actuator; and a protective member. Pressure chambers form pairs of the pressure chambers arranged in a second direction. Each of the pressure chamber pairs includes a first pressure chamber and a second pressure chamber that communicate with an identical nozzle via a communication channel. The protective member includes first partition walls joined to a surface at a first side in a first direction of the piezoelectric actuator and separating accommodating spaces from each other. Each of the first partition walls is provided between the first pressure chamber and the second pressure chamber, which belong to different pressure chamber pair, in the second direction. Each of the first partition walls is not provided between the first pressure chamber and the second pressure chamber, which belong to an identical pressure chamber pair, in the second direction.

A method for operating a printhead of a continuous inkjet printer comprising: producing at least one ink jet in a cavity of the print head; electrostatically separating drops or sections of one or more of the jet intended for printing from drops or sections that do not serve for printing; exiting from the cavity drops or sections of ink intended for printing, through a slot open on the outside of the cavity; and circulating at least one flow of air along the outlet slot of the cavity in a direction essentially perpendicular to at least one jet of ink emitted by the printhead and intended for printing. The air having a water vapor pressure lower than the water vapor pressure defined by 100% relative humidity at the coldest temperature of the printer.

In example implementations, a method is provided, which may include providing a carrier, applying a thermal release tape over the carrier, attaching a print head die, a drive integrated circuit (IC) and an interposer on the thermal release tape, wherein the print head die comprises ink feed holes formed in a back surface of the print head die, encapsulating the print head die, the drive IC and the interposer with an epoxy molded compound (EMC), removing the carrier and the thermal release tape, and forming a slot over an area of the EMC that covers the ink feed holes, wherein the ink feed holes are to be fluidically coupled to the slot.

A method includes applying a mold chase to a fluid ejection die to at least partially define at least one cavity. The mold chase includes a feature to contact a fluid ejection portion of the fluid ejection die, and at least one structure separate from the feature to contact a first end portion adjacent a first end of the fluid ejection die. The method includes filling the at least one cavity with a mold compound to produce a molded carrier for the fluid ejection die.

An aqueous ink jet ink composition according to the present embodiment is an aqueous ink jet ink composition for use in an ink jet recording method that includes ejecting ink from an ink jet head. The ink jet head includes nozzles that have a side wall surface, and the side wall surface has a scalloped shape in which a scallop width S1 and a notch depth S2 satisfy S1/S2≥4. The aqueous ink jet ink composition includes a self-dispersed pigment and a solvent that includes a compound represented by formula (1) below.
R.sub.1—O—R.sub.2—OH  (1) In formula (1), R.sub.1 represents a hydrogen atom, a methyl group, or an ethyl group, and R.sub.2 represents a divalent saturated hydrocarbon group having 5 or fewer carbon atoms or represents a group represented by formula (2) below.
R.sub.3—O—R.sub.4  (2) In formula (2), R.sub.3 and R.sub.4 each independently represent a divalent saturated hydrocarbon group having 2 or 3 carbon atoms.

A method includes applying a mold chase to a fluid ejection die to at least partially define at least one cavity. The mold chase includes a feature to contact a fluid ejection portion of the fluid ejection die, and at least one structure separate from the feature to contact a first end portion adjacent a first end of the fluid ejection die. The method includes filling the at least one cavity with a mold compound to produce a molded carrier for the fluid ejection die.