Abstract: Provision of a thermally sensitive recording medium made up of an undercoating layer containing a pigment and a binder as main components and a thermally sensitive color-developing layer containing a colorless or pale-colored basic leuco dye and a color-developing agent which develops a color by reacting with said basic leuco dye as main components on a substrate, wherein the undercoating layer contains a water-retention agent and a pigment whose oil-absorbing capacity prescribed by JIS K 5105 is from 80 cc/100 g to 120 cc/100 g as a pigment. Further, the solids concentration of a coating for the undercoating layer is from 25% to 45% and the dynamic water-retention capacity, which is Water retention measured with AA-GWR, is 350 g/m2 or less.

Abstract: A thermally sensitive recording medium has at least one layer on a substrate which is a thermally sensitive recording layer that contains a colorless or pale colored electron-donating leuco dye and an electron-accepting color-developing agent. At least one layer on the substrate contains a hydrated silicic acid compound which is treated by wet grinding treatment in a deposition process of the hydrated silicic acid compound. A thermally sensitive recording medium of high brightness, which is superior in color-developing sensitivity and coating layer strength and, further, has excellent head abrasion resistance, less debris adhering and sticking resistance is obtained.

Abstract: A thermally sensitive recording medium characterized to be superior in writing aptitude, printing aptitude, causes less head debris, possesses good water resistance, causes less sticking and is excellent in preservative stability of developed color in nature environment such as heat, water, humid or light, to sebum when handled with hand, oils, plasticizers and solvents can be obtained by following method, that is, a method for preparation of a thermally sensitive recording medium possessing a coating layer formed by applying a coating (A) containing a binder and a coating (B) containing a crosslinking agent on a thermally sensitive recording layer, which is formed on a substrate, and said thermally sensitive recording layer contains a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent comprising, forming an over coating layer by applying said coating (A) and coating (B) separately in accordance with a curtain coating method, wherein the formation of the ove

Abstract: A thermally sensitive recording medium whose luster of printed part is excellent can be provided by a thermally sensitive recording medium of single layer or multi layers having at least a thermally sensitive recording layer that contains a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent on a substrate comprising, containing a pigment whose aspect ratio is 30 or more in at least one layer formed on a substrate.

Abstract: A thermally sensitive recording medium whose luster of printed part is excellent can be provided by a thermally sensitive recording medium of single layer or multi layers having at least a thermally sensitive recording layer that contains a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent on a substrate comprising, containing a pigment whose aspect ratio is 30 or more in at least one layer formed on a substrate.

Abstract: A thermally sensitive recording medium comprising, single or multi layers, wherein, at least one layer on a substrate is a thermally sensitive recording layer that contains a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent, further, at least one layer on the substrate contains hydrated silicic acid compound which is treated by wet grinding treatment in deposition process of the hydrated silicic acid compound, thus, obtain a thermally sensitive recording medium of high brightness, which is superior in color developing sensitivity and coating layer strength, further excellent in head abrasion resistance, less debris adhering and sticking resistance

Abstract: Provision of a thermally sensitive recording medium comprising an undercoating layer containing a pigment and a binder as main components and a thermally sensitive color developing layer containing colorless or pale colored basic leuco dye and a color developing agent which develops color by reacting with said basic leuco dye as main components on a substrate, wherein said undercoating layer contains a water-retention agent and a pigment whose oil absorbing capacity prescribed by JIS K 5105 is from 80 cc/100 g to 120 cc/100 g as a pigment, further solid concentration of a coating for the undercoating layer is from 25% to 45% and dynamic water-retention capacity, which is Water retention measured with AA-GWR, is 350 g/m2 or less.

Abstract: A surface-treatment agent containing at least one type of processed starch selected from a) to c) as listed below is applied to a base paper of a newspaper so that a product of a B-type viscosity of the surface-treatment agent, measured under conditions of 10% concentration at 50° C. (rotor No. 1 at 60 rpm), and an application amount of the surface-treatment agent (both sides) is within a range of 2 to 15 cps·g/m2; a) Etherified starch, which is etherified by the compound defined in the general formula (1) given below: (AO)nH??(1) wherein A represents an ethylene group or propylene group, while n represents an integer of 1 to 15, b) Carboxylic acid esterified starch, which is esterified by monocarboxylic acid or dicarboxylic acid containing a linear, branched or cyclic alkyl group or alkenyl group having carbon atoms of 4 to 18, and c) Aldehyde starch.

Abstract: A surface-treatment agent containing at least one type of processed starch selected from a) to c) as listed below is applied to a base paper of a newspaper so that a product of a B-type viscosity of the surface-treatment agent, measured under conditions of 10% concentration at 50° C. (rotor No.