Ink jet ink set

#This invention relates to an inkjet ink set for inkjet printing that uses an anthrapyridone dye mixture as a colorant in a magenta ink.

#Ink jet printing is a non-impact method for producing images by the deposition of ink droplets in a pixel-by-pixel manner to an image-recording element in response to digital signals. There are various methods which may be utilized to control the deposition of ink droplets on the image-recording element to yield the desired image. In one process, known as continuous inkjet, a continuous stream of droplets is charged and deflected in an imagewise manner onto the surface of the image-recording element, while unimaged droplets are caught and returned to an ink sump. In another process, known as drop-on-demand ink jet, individual ink droplets are projected as needed onto the image-recording element to form the desired image. Common methods of controlling the projection of ink droplets in drop-on-demand printing include piezoelectric transducers and thermal bubble formation. Ink jet printers have found broad applications across markets ranging from industrial labeling to short run printing to desktop document and pictorial imaging.

#The inks used in the various inkjet printers can be classified as either dye-based or pigment-based. A dye is a colorant, which is dissolved in the carrier medium. A pigment is a colorant that is insoluble in the carrier medium, but is dispersed or suspended in the form of small particles, often stabilized against flocculation and settling by the use of dispersing agents. The carrier medium can be a liquid or a solid at room temperature in both cases. Commonly used carrier media include water, mixtures of water and organic co-solvents and high boiling organic solvents, such as hydrocarbons, esters, ketones, etc.

#Magenta Inks

#Ink 1 of the Invention

#Ink 1 of the invention was prepared using Dye A described above at 3.6 weight % of the ink composition, Dye B at 0.84 weight % of the ink composition, glycerol at 11.5 wt. %, diethylene glycol at 11.5 wt. %, triethylene glycol monobutyl ether at 7.5 wt. %, triethanolamine at 0.9 wt. % and the balance water.