Abstract: In a printing apparatus, a full-multi-type printing apparatus, and an ink jet printing apparatus of the present invention, if a heating device is used to heat a printing medium near a print head performing a printing operation by ejecting ink, the heating device is provided under a back surface of the printing medium located opposite to a face of the print head except for neighborhoods of ejection ports for printing material.

Abstract: There are provided a plain paper mode in which printing is performed on a plain paper and a special medium mode in which printing is performed on a special printing medium having a coat layer formed thereon. In the plain paper mode, Bk ink using both self-dispersing type pigment and dye as coloring materials is ejected from a Bk head , then a processing liquid with a high penetrability which insolubilizes the above coloring materials is ejected from a S head. On the other hand, in the special medium mode, the above Bk ink is ejected from the Bk head, but no processing liquid is ejected from the S head. As a result, this enables the improvement in a print quality, such as OD level, and a high-speed fixing in ink-jet printing in either case where a printing medium having a coat layer formed thereon is used or where the plain paper is used.

Abstract: An ink-jet printing method for obtaining higher quality printed Images by utilizing an ink-jet recording technology using a pigment ink and a treatment liquid. A treatment liquid for unstabilizing the dispersed condition of the pigment in the aqueous medium is applied onto the printing medium, and subsequently either an ink containing a self-dispersion type pigment and a pigment dispersed by a polymeric dispersant or an ink containing a self-dispersion type pigment and an ink containing a pigment dispersed by a polymeric dispersant are applied together to the printing medium in such a way that the treatment liquid and the inks are mixed in a liquid state on the printing medium to make the pigments indissoluble.

Abstract: In an ink jet printing apparatus that performs printing by using an ink and a processing liquid that renders the ink insoluble, an effect the mist of the processing liquid or substances insolubilized by it has on the ejection performance of the ink head or processing liquid head is reduced. The distance between the processing liquid head 101S and the print paper 103 carried by the belt 111 is set larger than the head-to-paper distances of other heads 101Bk, 101C, 101M, 101Y. As a result, the mist generated by the ejection of the processing liquid from the head 101S diffuses in a recessed space formed by the heads 101Bk and 101C on both sides of the head 101S and thus hardly reaches the ink nozzle surfaces of these heads on both sides.

Abstract: In an ink jet printing apparatus, black characters or the like can be printed with high density and little feathering as well as with high fixing capability, and images can be printed which are subject to little bleeding between a boundary between a black image, particularly a black character, and a color image. More specifically, a processing liquid is ejected onto a black ink on a dot-on-dot basis, and in an area onto which color inks are ejected, the processing liquid is not applied to pixels in eight neighborhoods of pixels onto which the black ink is ejected. Thus, no processing liquid is present at the boundaries between a black area and a color area, then a reactant between the black ink and the processing liquid or the like is prevented from flowing out to the peripheries of the boundaries, thereby reducing bleeding at the boundaries between the color image and the black image, when the color inks are applied to the peripheries.

Abstract: A processing liquid containing an insolubilizer of polymer as the insolubilizer is thinned out at a relatively low printing ratio, i.e., at a given ratio relative to dots of a black ink and applied after the Bk ink is applied. Thereby, a reacting product is fixed in a part relatively shallow and close to the surface of a printing medium without diffusing deep into the medium and thus can increase optical density of a printed &phgr; image. In this case, the fixation can be accelerated when the processing liquid is highly penetrative.

Abstract: Provided is an ink-jet printing method comprising the steps of penetrating a treating liquid which contains a component to react chemically with a pigment in an ink and has a penetrability onto a surface layer of a printing medium and the impacting ink-droplets containing the pigment to a portion among a whole surface of the printing medium where the treating liquid has been imparted, wherein a penetrating depth of the pigment applied to the treating liquid on the surface layer of the printing medium is deeper than a penetrating depth of the pigment alone applied to the printing medium on which no treating liquid is imparted and is shallower than a penetrating depth of the treating liquid.

Abstract: A process for carrying out printing using a dye-based ink, a pigment-based ink and a treatment liquid for making these inks insoluble. The process employs two inks of a pigment-based ink Ip and an dye-based ink Id and includes the steps of applying the pigment-based ink Ip to a printing medium P, applying the dye-based ink Id so as to overlap the pigment-based ink, mixing them on the printing medium P, and then further applying the treatment liquid S for making these inks insoluble. Alternatively, the process employs an ink Im containing a pigment and a dye mixed therein which requires no dispersant and includes the step of applying this mixed ink Im to a printing medium P followed by applying a treatment liquid S for making the ink Im insoluble. Consequently, high quality printing can be achieved.

Abstract: A process for preparing a polyhydroxycarboxylic acid having a weight average molecular weight of 50,000 to 1,000,000, which comprises a crystallizing step comprising (A) a step of heating pellets of a polyhydroxycarboxylic acid having a weight average molecular weight of 2,000 to 100,000 under stirring to a temperature from glass transition point or higher to a melting point or lower and heating until a defined result is attained, and (B) a step of heating the polyhydroxycarboxylic acid to a temperature of solid phase polycondensation reaction temperature, and a solid phase polycondensation reaction step of reacting the crystallized polyhydroxycarboxylic acid at an endothermic start temperature or lower of an endothermic peak as recognized upon temperature elevation analysis of the crystallized polyhydroxycarboxylic acid by using a differential scanning calorimeter.

Abstract: The present invention provides an ink jet printing apparatus and a preliminary ejecting method. In both a full-line and a serial printer, the amount of ink passing through nozzles of print heads is sometimes decreased below a normal value before and during actual printing, In the printer of present invention, a preliminary ejecting operation is performed taking the opportunity in which the amount of ink passing through nozzles is decreased below a normal value. Then, the amount of ink passing through nozzles recovers to the normal value at an ink ejection after the preliminary ejecting operation. Since only a small amount of ink is ejected through the nozzles during the preliminary ejection operation, dots formed on a print sheet are not noticeable. Further, it is unnecessary to move the print heads to a home position where an ejection recovering process is executed to remove ink having an increase viscosity.

Abstract: In an image printed by a printing apparatus, graininess particularly in a light part of the printed image is reduced by relatively simple structure by using a second color. To do so, magenta and cyan color component data in image data is subjected to under color removal to generate image data of a blue ink being the secondary color. On the basis of the data of the blue ink replaced for magenta and cyan, printing is performed by forming dots of the blue ink. At this time, black data is distributed into dark black and light black by density distribution, and the light black is substituted by the blue and yellow inks, whereby it is possible by the simple structure to prevent the graininess appeared when the cyan and magenta dots mutually appear biasedly and the graininess due to the black ink dots.

Abstract: A secondary color is used for printing an image with a printer so that the granularity of the printed image, particularly the light image area, can be reduced. Data of magenta and cyan color components of image data is subjected to the under removal process to generate blue ink image data of the secondary color. In accordace with the blue ink data for replacing the magenta and cyan data, a blue ink dot is printed. It is therefore possible to reduce the granularity to be caused by localized distributions of magenta and cyan dots.

Abstract: Disclosed herein is an ink comprising a first pigment, a second pigment and a dispersant, both of the pigment being dispersed in an aqueous medium, wherein the first pigment is a self-dispersing pigment having an anionic group or a cationic group, the group being bonded directly or through an atomic group to a surface of the pigment, the second pigment is a pigment dispersible in an aqueous medium with the dispersant, and the dispersant is an ionic polymeric dispersant having a same polarity as that of the group bonded to the surface of the pigment or a nonionic polymeric dispersant.

Abstract: An ink jet printing method and apparatus using a color ink and a print performance improving ink which minimizes an image quality degradation due to blank lines formed by failed or faulty nozzles. This system enables the use of a print head even with failed or faulty nozzles by minimizing the image quality degradation and extends the life of the print head before replacement. The print performance improving ink is deliberately ejected onto a blank line or its vicinity to produce the so-called primer effect, thereby inducing the color ink dots on the lines adjoining the non-ejecting nozzle line to spread into the blank line to make the blank line undistinguishable.

Abstract: High quality images showing an excellent fixation are formed by an ink-jet recording method using pigment inks. An ink set for the ink jet-recording method comprises a first ink containing an anionic dye in an aqueous medium, a second ink containing an anionic dye and having a lower coloring material content than the first ink and a dispersion destabilizing substance, and a third ink containing a self-dispersible first pigment, a second pigment and a polymeric dispersant for dispersing the second pigment in an aqueous medium. The dispersion destabilizing substance destabilizes the dispersion stability of at least either the first pigment or the second pigment in the third ink when the second ink and the third ink are brought into contact with each other. The second ink and the third ink are applied onto a printing medium one after another or substantially simultaneously so that they are brought into contact with each other in a liquid state on the printing medium.

Abstract: An ink-jet printing method for obtaining higher quality printed images by utilizing an ink-jet recording technology using a pigment ink and a treatment liquid. A treatment liquid for unstabilizing the dispersed condition of the pigment in the aqueous medium is applied onto the printing medium, and subsequently either an ink containing a self-dispersion type pigment and a pigment dispersed by a polymeric dispersant or an ink containing a self-dispersion type pigment and an ink containing a pigment dispersed by a polymeric dispersant are applied together to the printing medium in such a way that the treatment liquid and the inks are mixed in a liquid state on the printing medium to make the pigments indissoluble.

Abstract: An ink jet printing apparatus and an ink jet printing method for obtaining higher-quality printing with a pigment ink and a treating liquid, characterized in that the ink jet printing apparatus comprises an ink ejection portion, a treating liquid ejection portion, and a control device for controlling the above ink ejection portion and the above treating liquid ejection portion so as to provide the treating liquid onto the printing medium only after the ink was provided thereon, and the control device controls in such a manner that the application of the treating liquid is carried out during in the recording operation.

Abstract: An ink which comprises a first pigment, a second pigment, a polymer dispersant and an aqueous medium; wherein the first pigment is a self-dispersing pigment having on its surface at least one anionic group bonded to the surface directly or via an atomic group, the second pigment is dispersed in the aqueous medium by the polymer dispersant, and the polymer dispersant contains benzylmethacrylate as a monomer unit, or the polymer dispersant contains benzylmethacrylate as a monomer unit. Diffusion of this ink in the printing medium is suppressed in the cross-sectional direction but not horizontal direction. Thus, the ink can form an ink dot that has a proper dot size, uniform and high density in the dot, with little feathering or blur.

Abstract: Disclosed are polyester pellets made of a polyester which comprises dicarboxylic acid constituent units derived from dicarboxylic acids containing terephthalic acid and isophthalic acid and diol constituent units derived from diols containing ethylene glycol and 1,3-bis(2-hydroxyethoxy)benzene, and which has the properties: constituent units derived from terephthalic acid are 15 to 99.5% by mol and constituent units derived from isophthalic acid are 0.5 to 85% by mol, both based on the total amount of dicarboxylic acid isophthalic acid constituent units (i); constituent units derived from ethylene glycol are 25 to 99.5% by mol and constituent units derived from 1,3-bis(2-hydroxyethoxy)benzene are 0.5 to 75% by mol, both based on the total amount of the diol constituent units (ii); the intrinsic viscosity is in the range of 0.5 to 1.5 dl/g; and the melting point (Tm (°C.)), as measured by a differential scanning calorimeter, satisfies the formula [1/527−0.

Abstract: An ink-jet printing process which comprises the steps of applying one or two inks on a recording medium, and applying a treating liquid reactive with the ink prior to the ink application, wherein the ink contains a first pigment and a second pigment dispersed in an aqueous medium, or two inks each contains the first pigment and the second pigment respectively, wherein the first pigment is a self-dispersing pigment having anionic groups or cationic groups bonded directly or through another atomic group to the surface of the pigment; and the second pigment can be dispersed in an aqueous medium by a polymer dispersant, the ink further contains a dispersant for disperse the second ink where the dispersant is a nonionic dispersant or a dispersant having the same polarity as that of the group bonded to the surface of the first pigment, and the treating liquid.