Ink-jet media porous coatings with chemically attached active ligands

#The present invention is drawn to silica coatings for ink-jet media having chemically attached ultraviolet blockers, metal chelating agents, and/or hindered amine light stabilizers.

#In recent years, computer printer technology has evolved to a point where high resolution images can be transferred on to various types of media, including paper. One particular type of printing involves the placement of small drops of a fluid ink onto media surfaces in response to a digital signal. Typically, the fluid ink is placed or jetted onto the surface without physical contact between the printing device and the surface. Within this general technique, the specific method that the ink-jet ink is deposited onto the printing surface varies from system to system, and can include continuous ink deposit or drop-on-demand ink deposit.

#With regard to continuous printing systems, inks used are typically based on solvents such as methyl ethyl ketone and ethanol. Essentially, continuous printing systems function as a stream of ink droplets that are ejected and directed by a printer nozzle. The ink droplets are directed additionally with the assistance of an electrostatic charging device in close proximity to the nozzle. If the ink is not used on the desired printing surface, the ink is recycled for later use. With regard to drop-on-demand printing systems, the ink-jet inks are typically based upon water and glycols. Essentially, with these systems, ink droplets are propelled from a nozzle by heat or by a pressure wave such that all of the ink droplets ejected are used to form the printed image.

#Before the present invention is disclosed and described, it is to be understood that this invention is not limited to the particular process steps and materials disclosed herein because such process steps and materials may vary somewhat. It is also to be understood that the terminology used herein is used for the purpose of describing particular embodiments only. The terms are not intended to be limiting because the scope of the present invention is intended to be limited only by the appended claims and equivalents thereof.

#As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the content clearly dictates otherwise. “Light fast” or “color fast” refers to the quality of the printed image. Thus, the printed images printed on the ink-jet ink media of the present invention tend to retain their color density and detail (as well as show significantly less fading) when exposed to light, e.g., ultraviolet light, as compared to a standard printed image.

#“Humid fast” refers to the ability of a printed image to retain is image quality in damp conditions.