Provided are an ink composition for writing instruments which has a good solubility of a coloring material in an ink solvent and which is less liable to cause bleeding and feathering on the written lines and is improved in a water resistance, and a coloring material used for preparing the above ink composition. The coloring material includes a material obtained by adding at least one selected from a leuco dye, a halochromic dye and a photochromic compound to a compound represented by the following Formula (I): ##STR00001##
The ink composition for writing instruments is characterized by containing the coloring material described above.

A marking system comprises a substrate having a surface coated with a color-triggering developer and a deactivating ink composition; and a marking composition comprising at least one color precursor. At least one “non-color developing portion” of the surface is coated with both the color-triggering developer and the deactivating ink composition, and at least one “color-developing portion” of the surface is coated with the color-triggering developer and is not coated with the deactivating ink composition. Color development occurs at the color-developing portion(s) and does not occur at the non-color developing portion(s) upon application of the marking composition to the surface of the substrate.

A marking system comprises a substrate having a surface coated with a color-triggering developer and a deactivating ink composition; and a marking composition comprising at least one color precursor. At least one “non-color developing portion” of the surface is coated with both the color-triggering developer and the deactivating ink composition, and at least one “color-developing portion” of the surface is coated with the color-triggering developer and is not coated with the deactivating ink composition. Color development occurs at the color-developing portion(s) and does not occur at the non-color developing portion(s) upon application of the marking composition to the surface of the substrate.

Disclosed is a photochromic composition comprising a naphthopyran-based photochromic compound having a specific structure and an oligomer.

Disclosed is a photochromic composition comprising a naphthopyran-based photochromic compound having a specific structure and an oligomer.

Provided are thermochromic color-memorizing composition and thermochromic color-memorizing microcapsule pigment encapsulating the same, the thermochromic color-memorizing composition including: (a) an electron-donating color-developing organic compound; (b) an electron-accepting compound; and (c) an ester compound represented by the following formula (1) as a reaction medium which controls color reaction between the components (a) and (b):

##STR00001##

Provided are thermochromic color-memorizing composition and thermochromic color-memorizing microcapsule pigment encapsulating the same, the thermochromic color-memorizing composition including: (a) an electron-donating color-developing organic compound; (b) an electron-accepting compound; and (c) an ester compound represented by the following formula (1) as a reaction medium which controls color reaction between the components (a) and (b):

##STR00001##

Scrub resistant inks and methods and apparatus for fabrication and use thereof are provided. Scrub-resistant ink compositions may include a dye for marking skin; and a solvent dissolving a marking effective amount of the dye, wherein the solvent comprises about 0.1 to about 90 percent of a polar aprotic solvent. Apparatus for marking patients may include an ink reservoir; an ink dispenser having a fluid connection to the ink reservoir to dispense the ink at a desired rate to mark a patient; and a scrub resistant ink disposed in the ink reservoir. Methods for forming scrub-resistant ink compositions may include providing a marking effective amount of a dye suitable for use in marking skin; and mixing the dye with a first solvent comprising 0.1% to 90% of a polar aprotic solvent. Methods of marking patients may include applying an ink as recited above to a body part of the patient.

Scrub resistant inks and methods and apparatus for fabrication and use thereof are provided. Scrub-resistant ink compositions may include a dye for marking skin; and a solvent dissolving a marking effective amount of the dye, wherein the solvent comprises about 0.1 to about 90 percent of a polar aprotic solvent. Apparatus for marking patients may include an ink reservoir; an ink dispenser having a fluid connection to the ink reservoir to dispense the ink at a desired rate to mark a patient; and a scrub resistant ink disposed in the ink reservoir. Methods for forming scrub-resistant ink compositions may include providing a marking effective amount of a dye suitable for use in marking skin; and mixing the dye with a first solvent comprising 0.1% to 90% of a polar aprotic solvent. Methods of marking patients may include applying an ink as recited above to a body part of the patient.

Disclosed herein are printable compositions that include a UV-A blocking compound, wherein the composition is free of colorants that are visible under white light or UV light. Also disclosed herein are images formed by printing the printable composition on a substrate surface, wherein the substrate surface includes one or more Uv fluorescent materials on at least a portion thereof. Also disclosed herein are methods of forming an image on a substrate including printing a selected amount of the printable composition on top of a UV fluorescent material.