Abstract: An ink jet recording sheet comprising a support, at least one ink-receiving layer formed on the support, and a gloss-providing layer formed on the ink-receiving layer, said ink-receiving layer consisting essentially of a pigment and a binder, and said gloss-providing layer consisting essentially of a pigment and a synthetic polymer latex as a binder and having a glossy surface with a 75.degree. specular gloss of at least 25% as stipulated in JIS-Z8741, wherein at least 70 parts by weight in 100 parts by weight of the pigment in the gloss-providing layer are constituted by colloidal particles having an average particle size of at most 300 nm.

Abstract: An ink jet recording sheet which includes a support comprising wood fibers and pigment and at least one ink-receiving layer provided on the support, wherein content of the pigment in the support is 5-36% by weight and the recording sheet has an internal bond strength of 150-455 g/cm. A method for producing the ink jet recording sheet is also provided. This ink jet recording sheet is less in waviness of the sheet, spread of ink dots and stain in background after ink jet recording.

Abstract: An ink jet recording sheet which includes a support including a wood pulp and a pigment, an ink-receiving layer provided on one side of the support and a backcoat layer provided on the other side of the support, wherein the backcoat layer contains a binder containing a synthetic polymer having a glass transition temperature of -50.degree. to +25.degree. C. and at least one water-soluble binder selected from a starch, a polyvinyl alcohol and a cellulose derivative. The ink jet recording sheet is less in undulation caused by absorption of ink after ink jet recording and has a curling resistance hardly susceptible to change in temperature and humidity.

Abstract: Disclosed is an ink jet recording sheet which includes a support mainly composed of a wood pulp and a filler and provided with at least one ink-receiving layer with or without a backcoat layer wherein the ratio of gas permeability/density of the recording sheet is within a specific range. Further disclosed is a method for producing it. The ink jet recording sheet can provide images high in density, excellent in color quality and sharpness and less in feathering, is less in strike-through of ink and cockling and has good image reproducibility.

Abstract: An ink jet recording sheet comprising a support, at least one ink-receiving layer formed on the support, and a gloss-providing layer formed on the ink-receiving layer, said ink-receiving layer consisting essentially of a pigment and a binder, and said gloss-providing layer consisting essentially of a pigment and a synthetic polymer latex as a binder and having a glossy surface with a 75.degree. specular gloss of at least 25% as stipulated in JIS-Z8741, wherein at least 70 parts by weight in 100 parts by weight of the pigment in the gloss-providing layer are constituted by colloidal particles having an average particle size of at most 300 nm.

Abstract: The present invention provides an ink jet recording sheet which includes a support and an ink-receiving layer coated on at least one side of the support wherein the ink-receiving layer contains a coating composition containing a quaternary salt of dimethylamine.multidot.epichlorohydrin adduct represented by the following formula (1): ##STR1## wherein n shows a polymerization degree and is a positive number in the range of 2 to 2000. The ink-receiving layer may additionally contain a (meth)acrylamide-diallylamine copolymer for further effectively inhibiting the color degradation of the image.

Abstract: Disclosed is an ink jet recording sheet which comprises a support mainly composed of wood fibers, an ink-receiving layer provided on one side of the support and a tacky layer provided on another side of the support where a barrier layer comprising a film-forming material is provided between-the support and the ink-receiving layer and/or between the support and the adhesive layer. Spread of ink due to penetration of the adhesive into the ink-receiving layer is prevented and images excellent in sharpness and color quality can be obtained.

Abstract: There is discloses a magnetic recording sheet comprising a substrate, a magnetic recording layer formed on one side of the substrate, an image recording layer formed on the other side of the substrate, a first subbing layer formed between the substrate at the magnetic recording layer, and preferably, a second subbing layer formed between the substrate and the image recording layer, said magnetic recording layer comprising a magnetic powder and an aqueous binder, said image recording layer comprising a binder, and said first and second subbing layers comprising a styrene-butadiene latex having a gel content of 5 to 75%. This magnetic recording sheet can be obtained without any trouble in its production process and is excellent in dimensional stability, magnetic recording properties, image-recording properties, etc.

Abstract: An alkaline paper is produced by adding a cationic starch containing an alkyltetrahydro-1,3,5-2H-thiadiazine-2-thione or a bromonitroalcohol, and an alkylketene dimer to a paper stock. Formation of slime in the paper stock system is substantially inhibited and an alkaline paper excellent in sizing characteristics and safety to man is obtained.

Abstract: Disclosed is a coat type ink jet recording sheet which has on one side of a support a backcoat layer containing a specific platy inorganic pigment and on another side an ink-receiving layer containing at least one of starch particles, modified starch particles and ethylene-vinyl acetate copolymer resins, and a specific cationic dye fixing agent in such an amount as providing a specific cation charge per unit area of the recording sheet. This ink jet recording sheet is less in curling and cockling in wide ranges of temperature and humidity, improved in runnability on recording apparatuses, high in light resistance and ozone resistance of recorded images and in adhesion of the coating layers, less in blotting of overlapped color ink dots of the recorded images and besides, hardly undergoes yellowing.

Abstract: A carbonless paper produced by using, as leuco dye solution-containing microcapsules, synthetic high molecular wall membrane microcapsules and, as a color developing agent, an inorganic solid acid gives smooth printing when used in letter printers. This paper has various advantages in printing by letter printers such as no attack for photosensitive plates or masters, no generation of offensive smells or fumes at the time of thermal fixation and no destruction of microcapsules in wet development.

Abstract: When a transferred image is formed on a plain paper by the use of a colorless backcarbon paper coated with an alcohol-based flexographic ink composed essentially of (A) microcapsules whose core substance is an oil droplet containing an electron-donating organic color former, (B) microcapsules whose core substance is an oil droplet containing an electron-accepting organic color developer, (C) a binder resin and (D) a solvent composed mainly of a lower alcohol of 1 to 3 carbon atoms, the density of the transferred image is improved by adding an appropriate amount of a wax to the core substance(s) of either or both of the above microcapsules (A) and (B).

Abstract: A pressure sensitive copying paper comprising a sheet having on a support a coating layer containing finely divided cellulose powder (a) and mononucelus microcapsules (b) containing an oil solution of an electron donative colorless or light-colored dye, using an amino resin as film material and having a volume-average particle diameter of 5-10 microns (.mu.m) and a film thickness of 0.08-0.3 microns (.mu.m); and a sheet having on a support a coating layer containing an electron acceptant solid-state acid material which is reacted on contact with the dye to form a color. This pressure sensitive copying paper has the advantages such as excellent color forming performance, proofness against smudging, long-time storage stability, etc.

Abstract: There is disclosed no-carbon copying paper composed fundamentally of a color former sheet produced by coating a support with microcapsules containing a colorless electron-donative organic compound as a color former and a color developer sheet produced by coating a support with a coating color containing activated clay as a color developer which adsorbs the aforesaid electron-donative organic compound to develop color. When said coating color is prepared by adding a polyvinyl alcohol, a styrene-butadiene latex and a wax emulsion to the activated clay, it becomes possible to apply it at a high concentration and there are accomplished the maintenance of surface strength of the color developer sheet, the decrease in stains on the blanket and the improvement in sunlight resistance of the colored characters and in the aptitude for pasting.

Abstract: A color-developing sheet for use in no-carbon copying system, which contains a layer of a combination of a solid acid with an acidic polymer is improved in preventing yellowing during the preservation thereof, in giving high color intensity and stability to image formed, by incorporating titanium dioxide into the layer.

Abstract: The present invention provides an ink jet recording sheet which includes a support and an ink-receiving layer coated on at least one side of the support wherein the ink-receiving layer contains a coating composition containing a quaternary salt of dimethylamine.multidot.epichlorohydrin adduct represented by the following formula (1): ##STR1## wherein n shows a polymerization degree and is a positive number in the range of 2 to 2000. The ink-receiving layer may additionally contain a (meth)acrylamide-diallylamine copolymer for further effectively inhibiting the color degradation of the image.