A recording medium includes a substrate, a first ink-receiving layer, and a second ink-receiving layer adjacent to the first ink-receiving layer, in this order. The first ink-receiving layer has a positive surface zeta potential, and the second ink-receiving layer has a negative surface zeta potential. The thickness of the second ink-receiving layer is 2 μm to 15 μm.

A pretreatment liquid that can be used together with an aqueous inkjet ink comprising a pigment and water, wherein the pretreatment liquid comprises a coagulant (A), a surfactant (B), a resin (C) and water, the coagulant (A) comprises a metal salt that includes at least a polyvalent metal salt, the surfactant (B) comprises a polyoxyalkylene alkylamine represented by the following general formula (1).

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A nanofiber sheet has a nanofiber layer composed of an accumulation of nanofibers. The nanofiber sheet has a plurality of membrane-like regions which extend between the nanofibers. The membrane-like regions of the nanofiber sheet each contain a water insoluble polymer and a pigment. The water insoluble polymer contained in the membrane-like regions of the nanofiber sheet is different from a constituent member of the nanofibers. The nanofiber sheet is preferred because it has a plurality of membrane-like aggregate regions, each an aggregate of a plurality of membrane-like regions which are adjacent to each other via a fiber and it has a non-membrane-like region between the membrane-like aggregate regions adjacent to each other.

A nanofiber sheet has a nanofiber layer composed of an accumulation of nanofibers. The nanofiber sheet has a plurality of membrane-like regions which extend between the nanofibers. The membrane-like regions of the nanofiber sheet each contain a water insoluble polymer and a pigment. The water insoluble polymer contained in the membrane-like regions of the nanofiber sheet is different from a constituent member of the nanofibers. The nanofiber sheet is preferred because it has a plurality of membrane-like aggregate regions, each an aggregate of a plurality of membrane-like regions which are adjacent to each other via a fiber and it has a non-membrane-like region between the membrane-like aggregate regions adjacent to each other.

An ink that contains a water-insoluble colorant, an oxidized polyethylene wax, a compound that is represented by formula (1) or formula (2) and has an HLB value of 7.5-20.0, and water; an inkjet printing method that uses the ink; and a printing medium to which the ink is adhered. In the formulas, R.sup.1-R.sup.3 are each independently a linear or branched C7-C40 hydrocarbon group, EO is an ethyleneoxy group, and PO is a propyleneoxy group. m1 and m2 are average values and are 1-300, and n1 and n2 are average values and are 0-10.

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An ink that contains a water-insoluble colorant, an oxidized polyethylene wax, a compound that is represented by formula (1) or formula (2) and has an HLB value of 7.5-20.0, and water; an inkjet printing method that uses the ink; and a printing medium to which the ink is adhered. In the formulas, R.sup.1-R.sup.3 are each independently a linear or branched C7-C40 hydrocarbon group, EO is an ethyleneoxy group, and PO is a propyleneoxy group. m1 and m2 are average values and are 1-300, and n1 and n2 are average values and are 0-10.

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An embodiment of the present invention provides a transfer film that may be used for both a picking process and a placing process of an element, a transfer method using the transfer film, and an electronic product manufactured using the same. Here, the transfer film according to an embodiment of the present invention includes a base part, an adhesion part, and a first protrusion part. The adhesion part is provided on one surface of the base part, and at least part of the first protrusion part is formed and protruded on one surface of the base part to be accommodated inside the adhesion part, and the thickness increases toward the first direction parallel to the surface of the base part. The first protrusion part is partitioned into a first region including a relatively thick portion of the first protrusion part and a second region including a relatively thin first protrusion part and having weaker adhesive force than the first region, and the element is picked while the first region is lifted first in the picking process, while the element is placed while the second region is lifted first in the placing process.

A method of printing an image using a printing system having first and second printheads supplied with a same ink. The method includes the steps of: allocating first lines of the image to the first printhead; allocating second lines of the image to the second printhead; dithering the first lines of the image using a selected first dither mask; dithering the second lines of the image using a selected second dither mask; printing the dithered first lines of the image using the first printhead; and printing the dithered second lines of the image using the second printhead. The first and second dither masks are selected based on a relative alignment of the first and second printheads.

A radiation curable inkjet ink composition that includes (A) a mono-ethylenically unsaturated oligomer, (B) a mono-ethylenically unsaturated monomer, and (C) a solvent, wherein the radiation curable inkjet ink composition is substantially free of a photoinitiator and wherein a total weight of the mono-ethylenically unsaturated oligomer (A) is less than or equal to the total weight of the mono-ethylenically unsaturated monomer (B). A printed article including the radiation curable inkjet ink composition in cured form, and a method of forming an image with a thermal inkjet printhead are also provided.

A radiation curable inkjet ink composition that includes (A) a mono-ethylenically unsaturated oligomer, (B) a mono-ethylenically unsaturated monomer, and (C) a solvent, wherein the radiation curable inkjet ink composition is substantially free of a photoinitiator and wherein a total weight of the mono-ethylenically unsaturated oligomer (A) is less than or equal to the total weight of the mono-ethylenically unsaturated monomer (B). A printed article including the radiation curable inkjet ink composition in cured form, and a method of forming an image with a thermal inkjet printhead are also provided.