Compositions: coating or plastic – Coating or plastic compositions – Marking
Reexamination Certificate
2002-08-30
2004-07-20
Bell, Mark L. (Department: 1755)
Compositions: coating or plastic
Coating or plastic compositions
Marking
C106S031360, C427S466000, C428S195100
Reexamination Certificate
active
06764540
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to ink compositions whereby images with high qualities and high storage stability can be obtained. In particular, it relates to ink compositions favorably used in ink jet recording and an ink jet recording method with the use of the ink compositions.
BACKGROUND OF THE INVENTION
With the recent popularization of computers, ink jet printers have been widely used in printing on papers, films, fabrics, etc. not only for business purposes but also for household purposes.
There are a number of ink jet recording systems, for example, a system wherein liquid drops are jetted under the application of pressure by a piezoelectric device, a system wherein liquid drops are jetted by using ink bubbles formed by heating, a system with the use of ultrasonic wave, and a system wherein liquid drops are electrostatically sucked and jetted. As inks for these ink jet recording systems, use has been made of water inks, oily inks and solid (melting) inks. Among these inks, water inks have been mainly employed because of being favorable from the viewpoints of easiness in production and handling, smell, safety, etc.
It is required that colorants to be used in these inks for ink jet recording are highly soluble in solvents, enable high-density recording, have favorable color hues, are highly fast to light, heat, air, water and chemicals, have excellent fixation properties to image recording materials with little bleeding, excellent storage properties as inks, no toxicity and high purity, and can be economically obtained. However, colorants satisfying all of these requirements at high levels can be hardly found out.
Although there have been proposed various dyes and pigments for ink jet recording and already put into practical use, no colorant satisfying all of these requirements has been established so far. By using commonly known dyes or pigments with color index (C.I.) numbers, both of the color hues and fastness needed in ink jet recording inks can be hardly achieved.
On the other hand, Japanese Patent Laid-Open No. 74761/1983 and ibid. No. 92369/1985 disclose inks containing glycerol and ethylene oxide adducts of diethylene glycol and alcohols, and Japanese Patent Laid-Open No. 2000-265098 proposes to use ethylene oxide adducts of long chain linear alcohols. However, these inks suffer from a disadvantage that image qualities of images formed thereby are worsened during storage.
Furthermore, Japanese Patent Laid-Open 88048/1994, ibid. No. 333532/1996, ibid. No. 333533/1996, U.S. Pat. No. 5,837,043, ibid. U.S. Pat. No. 5,626,655, etc. propose that bleeding in images can be relieved by using inks containing ethylene oxide adducts of higher alcohols. However, these inks have other disadvantages such as frequently causing plugging and suffering from changes in color tones due to poor image storing properties.
SUMMARY OF THE INVENTION
The present invention provides ink compositions having a high jetting stability, being excellent color hue, weatherability and moisture resistance and showing favorable image qualities and an ink jet recording method with the use of the compositions.
The object of the present invention can be achieved by ink compositions and an ink jet recording method as will be specified by the following five items.
1) An ink composition made up of a dye dissolved or dispersed in an aqueous medium characterized in that the ink composition contains water, a water-miscible organic solvent, a dye and at least one compound capable of including a dye therein.
2) An ink composition according to the above 1) characterized in that the above-described compound capable of including a dye therein is a rotaxane molecule or a molecular nanotube.
3) An ink composition according to claim the above 1) or 2) characterized in that each of the compound capable of including a dye therein, rotaxane molecule and molecular nanotube has cyclodextrin as the constitutional unit.
4) An ink composition according to any of the above 1) to 3) characterized in that the ink composition is to be used in ink jet recording.
5) An ink jet recording method comprising jetting ink drops onto an image recording (receiving) material having an image recording layer containing inorganic pigment particles on a substrate in accordance with recording signals and thus recording an image on the image recording material, characterized in that the ink drops are made of an ink composition according to any of the above 1) to 4).
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in greater detail.
The ink composition according to the present invention, which is made up of an aqueous medium composed of water and a water-miscible organic solvent and a dye such as a water-soluble dye or oil-soluble dye dissolved or dispersed in the aqueous medium, contains at least one “compound capable of including a dye” (hereinafter referred to as an inclusion compound) together with the dye. Images (involving characters and diagrams) recorded by using the ink composition according to the present invention have excellent weatherability, which makes it favorable as an ink composition for ink jet recording.
In the present invention, an inclusion compound is defined as a compound which is capable of incorporating a dye molecule in its structure. The term “inclusion compound” means a compound which forms an inclusion lattice in case where two types of molecules are combined together under adequate conditions and one of these molecules forms a tunnel, layered or network structure (i.e., the inclusion lattice) while the other molecule is incorporated within the space (Iwanami Rikagakujiten, 5th ed., p. 1296 (1998)).
It is assumed that the inclusion compound contained in the ink composition according to the present invention has an effect of incorporating (including) the whole water-soluble or oil-soluble dye molecules or a part thereof contained (included) in the ink composition.
As the above-described inclusion compound, use can be made of rotaxanes, molecular nanotubes, crown compounds (18-crown-6,15-crown-5, dibenzo-14-crown-4, dicyclohexyl-18-crown-6, cryptand[2.2.2], etc.), cyclodextrins (&agr;-cyclodextrin, &bgr;-cyclodextrin, &ggr;-cyclodextrin, etc.), cyclophane, azacyclophane, calixarenes (calix[4]arene, calix[6]arene, calix[8]arene, etc.), cyclotriveratrylene, cavitand, oligopeptide, deoxycholic acid, perhydrotriphenylene, tri-O-thymotide, cyclophosphazene and so on.
In addition to the compounds as cited above, it is also possible to use compounds reported by Fumio Tokuni (Hosetsu Kagobutsu no Kiso to Oyo, NTS (1989)) and Naoya Ogata (Kinousei Chobunshi no Sekkei to Shorai Tenbo, CMC (1998)).
Particularly preferable examples of the inclusion compound to be used in the present invention are rotaxanes, molecular nanotubes, crown ethers, cyclodextrin, azacrown compounds and calixarenes.
In the present invention, it is particularly preferable to use rotaxane molecules and molecular nanotubes which are inclusion compounds having cyclodextrins bonded to each other in tandem (i.e., having cyclodextrin as a constitutional unit) and capable of including a dye therein.
Molecular nanotubes, which are publicly known compounds, are described in detail in Science (1994), 264 (5156), 249-251; J. Phys. Chem. (1996), 100(38), 15562-15568; Kobunshi Ronbunshu (1999), 56(12), 8330836; J. Chem. Phys. (2000), 112(9), 4321-4325;Langmuir (2000), 16(26), 10278-10280; J. Chem. Phys. (2001), 114(1), 1-3; etc.
As the constitutional unit of the molecular nanotubes, use can be made of various compounds such as &agr;-cyclodextrin, &bgr;-cyclodextrin and &ggr;-cyclodextrin.
The ink composition according to the present invention contains at least one “compound capable of including a dye therein”. It is preferable that the content of such a compound ranges from 0.1 to 60% by weight, still preferably from 1 to 40% by weight, in 100% by weight of the ink composition.
The ink composition according to the present invention can be produced by dissolving and/or dispersing a dye i
Bell Mark L.
Burns Doane Swecker & Mathis L.L.P.
Faison Veronica F.
LandOfFree
Ink compositions and ink jet recording method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ink compositions and ink jet recording method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ink compositions and ink jet recording method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3196720