Abstract: An ink can be substantially invisible under most lighting conditions, and only visible when excited by UV energy having a wavelength specific to the colorant. The ink can include a liquid vehicle and a fluorescent colorant. The fluorescent colorant can have an average particle size of less than about 200 nm. Such ink can be configured as an ink-jet ink.

Abstract: An ink can be substantially invisible under most lighting conditions, and only visible when excited by UV energy having a wavelength specific to the colorant. The ink can include a liquid vehicle and a fluorescent colorant. The fluorescent colorant can have an average particle size of less than about 200 nm. Such ink can be configured as an ink-jet ink.

Abstract: A print head for ink-jet printing including an orifice plate with an intermediate layer of reinforcement material bonded thereto, an ink barrier layer, and an adhesion promoter located between the intermediate layer and the barrier layer. The adhesion promoter bonds the intermediate layer to the barrier layer. Exemplary adhesion promoters include organosilane compositions, polyacrylic acid, polymethylacrylic acid, and mixtures thereof. Representative intermediate layers include oxidizable metals (e.g. chromium, tantalum, and mixtures thereof) and silicon-containing compositions (e.g. silicon dioxide, silicon nitride, silicon carbide, and mixtures thereof). In a process for making a print head, an adhesion promoter is applied to the orifice plate/intermediate layer combination which is thereafter bonded to the barrier layer using the adhesion promoter. All of these components are secured together through the application of pressure and heat.

Abstract: In accordance with the invention inks suitable for use in ink-jet printers and method for formulating the same are provided. More particularly, inks comprising the present dyes and buffers exhibit excellent color performance and lightfastness across a range of media. Furthermore, the inks enable good reliability in an environment having a relatively high concentration of precipitating agents. This reliability enables the use of precipitation bleed control mechanisms.

Abstract: A method for controlling color bleed in multi-color thermal inkjet printing systems. Color bleed involves the migration of coloring agents between adjacent zones in a multi-color printed image on a substrate. To control color bleed between any two ink compositions in a multi-ink system, at least one of the ink compositions will contain a precipitating agent (e.g. a multi-valent metal salt). The precipitating agent is designed to react with the coloring agent in the other ink composition of concern. As a result, when the two ink compositions come in contact, a precipitate is formed from the coloring agent in the other ink composition which prevents migration thereof and color bleed problems. This technique is applicable to printing systems containing two or more ink compositions, and enables distinct multi-color images to be produced without the problems normally caused by color bleed.

Abstract: Wet cockle is minimized in aqueous-based, thermal ink-jet inks by adding to the ink at least one water-soluble substance, such as a solvent or salt, having a molecular weight of less than 200 grams/mole in an amount sufficient to reduce the mole fraction of water to a maximum value of about 0.5. Addition of the substance reduces wet paper cockle to a value that is less than the distance between the thermal ink-jet pen and the paper, thereby preventing a crash condition between the paper and the pen.

Abstract: A method for controlling color bleed in multi-color thermal inkjet printing systems. Color bleed involves the migration of coloring agents between adjacent zones in a multi-color printed image on a substrate. To control color bleed between any two ink compositions in a multi-ink system, at least one of the ink compositions will contain a precipitating agent (e.g. a multi-valent metal salt). The precipitating agent is designed to react with the coloring agent in the other ink composition of concern. As a result, when the two ink compositions come in contact, a precipitate is formed from the coloring agent in the other ink composition which prevents migration thereof and color bleed problems. This technique is applicable to printing systems containing two or more ink compositions, and enables distinct multi-color images to be produced without the problems normally caused by color bleed.

Abstract: Inks are provided comprising (a) at least two dyes corresponding to the formula ##STR1## wherein W is COOH,X is H, or COOH,Y is H, COOH, or SO.sub.3 H,Z is H, COOH, or SO.sub.3 H, andR is H, CH.sub.2 COOH, or CH.sub.2 CH.sub.2 COOH;with the proviso that there are at least two COOH groups and that the number of COOH groups is equal to or greater than the number of SO.sub.3 H groups, and (b) a solvent which may be water or a mixture of water and a water-soluble organic solvent provide excellent waterfast prints on paper. The inks preferably have a pH from about 7 to about 9.5. Also preferably, a phosphate is added to reduce kogation and a metal chelating agent is added to further reduce nozzle clogging.