Brother Kogyo Kabushiki-kaisha

Brother Kogyo Kabushiki

Hideto Yamazaki

Shunichi Higashiyama

Masaya Fujioka

Masahito Kato

Takeo Kitahara

Masashi Tsuda

Michiko Aoyama

Hiromitsu Sago

Mayuko Umemura

Yoshito Toyoda

Kazuma Goto

Narumi Koga

Ryuji Kato

Tatsunosuke Hoshi

Mayuko Okada

Kazuo Kobayashi

Hideo Ohira

Noriatsu Aoi

Hidemasa Sawada

Disclosed is a combination of a water-based ink and a wetting solution for ink-jet recording, which enables smooth introduction of the water-based ink into an ink-jet head. One end of a capillary having an inner diameter of from about 0.1 to about 1 mm is dipped in the water-based ink so that the water-based ink rises inside the capillary. A combination of a water-based ink and a wetting solution that satisfy the following formula (1) is selected:&#x2267;about 2&#x2003;&#x2003;(1) wherein Vs indicates a rising speed of the water-based ink at an intermediate position before and after the water-based ink rising when an inner wall of the capillary is in a dry state, and Vi indicates a rising speed of the water-based ink when an inner wall of the capillary is wetted with the wetting solution.

Method for selecting water-based ink and wetting solution for ink-jet recording

A fluorescent water base ink for ink-jet recording includes water, a first fluorescent dye, and a second fluorescent dye. The first fluorescent dye absorbs light in a first absorption wavelength region in an ultraviolet region to emit fluorescence, and the first fluorescent dye absorbs light in a second absorption wavelength region to emit no fluorescence. The second fluorescent dye absorbs light in an absorption wavelength region in the ultraviolet region, which is different from the first absorption wavelength region of the first fluorescent dye, to emit fluorescence. A wavelength region of the fluorescence of the second fluorescent dye is not overlapped with the first absorption wavelength region of the first fluorescent dye, but at least a part of the wavelength region of the fluorescence of the second fluorescent dye is overlapped with the second absorption wavelength region. The fluorescence intensity of the ink is increased.

Fluorescent water base ink for ink-jet recording

A water base ink set for ink-jet recording includes a black ink containing a negatively charged self-dispersing black pigment and a water-soluble polyvalent alcohol alkyl ether; and a yellow ink containing a water-soluble anionic yellow dye in which a number of counter ion or ions per one molecule is not more than 3, a surfactant based on amine represented by the following general formula (1), and a water-soluble polyvalent alcohol alkyl ether;R&#x2014;N&#x2014;(CHCHO)H(CHCHO)H&#x2003;&#x2003;(1)

Water base ink set for ink-jet recording

A water base pigment ink for ink-jet recording contains a pigment, water, and at least one of polyethylene glycol and diglycerol. The ink is solidified into a solid matter when the water is evaporated. Further, the solid matter is redissolved in the unsolidified water base pigment ink for ink-jet recording. When the ink is used, then neither clog-up of a nozzle nor discharge failure is caused, no load is imposed by the solidified ink on the maintenance system such as the wiping equipment, and the sticking performance on the paper is satisfactory.

Water base pigment ink for ink-jet recording

A fluorescent water base ink for ink-jet recording contains a first fluorescent dye and a second fluorescent dye. The first fluorescent dye has a first ultraviolet absorption wavelength region in an absorption spectrum and a first fluorescence emission wavelength region in a fluorescence spectrum. The second fluorescent dye has a second ultraviolet absorption wavelength region which is different from the first ultraviolet absorption wavelength region in an absorption spectrum and a second fluorescence emission wavelength region in a fluorescence spectrum. The first fluorescent dye further has an absorption wavelength region which is different from the first ultraviolet absorption wavelength region and which overlaps at least a part of the second fluorescence emission wavelength region.

Fluorescent water-base ink for ink-jet recording

A fluorescent water base ink for ink-jet recording contains a fluorescent dye having a xanthene skeleton, and a glycol. In the fluorescent dye, the difference in hydrophilic index log P is not less than 2.6 between a substituent bonded to C-9 carbon atom of the xanthene skeleton and other portion of the fluorescent dye than the substituent bonded to the C-9 carbon atom. The glycol has a distance between hydroxyl groups substantially equivalent to or longer than an interatomic distance between atoms directly bonded to C-3 and C-6 carbon atoms of the xanthene skeleton of the fluorescent dye, respectively. It is assumed that the glycol is coordinated with the xanthene skeleton in a bridge form to increase the fluorescence intensity by increasing the electron density of the xanthene skeleton. The ink having high fluorescence intensity and in which the fluorescence intensity is not lowered in a time-dependent manner is provided.

A fluorescent water base ink for ink-jet recording to be used for an ink-jet printer contains water, a pigment, a compound having primary or secondary amide group, and a fluorescent dye represented by the following formula (1): wherein Rrepresents OH or N(R)R, Rrepresents hydrogen atom or halogen atom, and each of Rand Rrepresents hydrogen atom or alkyl group. A sufficient OD value and a fluorescence value are obtained while securing the vivid color development and the excellent water resistance principally in accordance with the interaction of the fluorescent dye and the compound having the amide group.

An ink set for ink-jet recording includes two or more inks each of which contains water, a coloring agent, and a water-soluble organic solvent. The ink set is prepared so that a ratio (Vmin/Vmax) between a maximum permeation velocity Vmax of the ink and a minimum permeation velocity Vmin of the ink is not less than 0.6 when the respective inks are developed by means of paper chromatography on a certain paper. It is possible to suppress the bleeding of a formed image.

Ink set for ink-jet recording and ink-jet recording method

A water base ink for ink-jet recording contains a self-dispersing type pigment, glycol ether, and water. In the glycol ether, the number of carbon atoms of an ethylene oxide moiety is not less than 8, and the solubility in water at 25&#xb0; C. is not less than 1%. The ink reduces the blurring of a recorded image which would be otherwise caused by the feathering on the paper surface. The ink is excellent in drying performance on the paper surface, and the ink makes it possible to stably disperse the pigment.

Water base ink for ink-jet recording

A water base ink for ink-jet recording, which is usable for an ink-jet recording apparatus having an ink-jet head provided therein with an ink flow passage formed of nickel or nickel alloy, includes a coloring agent, water, and a water-soluble organic solvent. The ink is blended so that a current density, which is obtained within an electric potential range of &minus;600 to &plus;300 mV, is not more than 100 &mgr;A/cm when anodic polarization measurement is performed by using a reference electrode of silver/silver chloride, a counter electrode of platinum, and a working electrode of nickel or nickel alloy. The ink does not corrode any part for constituting the flow passage in the ink-jet head.

Water base ink for ink-jet recording and ink-jet recording apparatus provided with the same

Water base pigment ink for ink-jet recording and ink-jet recording method

An ink for ink-jet recording of the present invention includes water and a pigment. A total amount of free monovalent metal is not more than 300 ppm in the ink, and a total amount of free divalent or polyvalent metal is not more than 5 ppm in the ink. The ink may further comprise an antiseptic/fungicidal agent. The ink is excellent in dispersion stability of the pigment. The ink is stably discharged from a head over a long period without causing any clog-up at an ink flow passage and a nozzle of the head of a recording apparatus.

Water base pigment ink for ink-jet recording and recording apparatus

An ink for ink-jet recording of the present invention includes a dispersion of a pigment, and an ink solvent containing a water-soluble organic solvent and glycol ether. The ink is prepared such that an Rf value, which represents a rate of flow of the pigment obtained when the pigment dispersion is developed with the ink solvent by means of paper chromatography, is not more than 0.5. The ink has a fast permeation speed, and hence the feathering and the bleeding are avoided.

Water base pigment ink for ink-jet recording and ink-jet recording apparatus

An inventive ink comprises a water-soluble dye or a pigment as a coloring agent, 5 to 15% by weight of polyvalent alcohol monoalkyl ether selected from the group consisting of tetraethylene glycol monoalkyl ethers and pentaethylene glycol monoalkyl ethers, 5 to 50% by weight of polyvalent alcohol, and pure water. When recording is performed in accordance with the ink-jet recording system by using the inventive ink, an excellent result is obtained from any viewpoint concerning, for example, the recording characteristic, the fixation to an objective recording material, the quick drying characteristic, the printing quality characteristic, and the low odor characteristic. The inventive ink is useful as an ink to be used for ink-jet recording apparatuses based on various recording systems, making it possible to obtain an excellent recording result.

Water based ink and ink-jet recording method

A recording ink composition comprises pure water, a water-soluble dye, a polyvalent alcohol, and phosphoric acid. When iron is contained as an impurity in the recording ink composition, the iron and phosphoric acid form a ferric (III) phosphato complex ion represented by �Fe(HP0.sub.4)(H.sub.2 O)!.sup.+. Owing to the formation of the complex ion, the recording ink composition is prevented from discoloration which would be otherwise caused by iron ion. Further, the recording ink composition is prevented from formation and deposition of iron compounds. Therefore, the obtained ink has an excellent color tone, and the ink avoids blocking at a nozzle of a printing head or the like of an ink-jet printer.

Growing community of inventors

Nagoya, Japan

Hideto Yamazaki