Heat-sensitive recording sheet

Claim 1

A heat-sensitive recording material comprising a support having thereon a color-developing layer which contains as main ingredient a colorless or pale colored basic chromogenic dye and an organic colordeveloping agent, wherein the color-developing layer comprises as the colorless or pale colored basic chromogenic dye at least one substance selected from the group consisting of a fluorane-type leuco dye represented by the following general formula (I) and a divinyl compound represented by the following general formula (II), and as a stabilizer at least one halogen-substituted zinc benzoate derivative represented by the following general formula (III): ##STR17## wherein at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 9 represents ##STR18## the remainders of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 9 , which may be the same or different, represent a hydrogen atom, an alkyl group, an alkoxy group, a cycloalkyl group, a halogen atom, a nitro group, a hydroxy group, an amino group, a substituted amino group, an aralkyl group, a substituted aralkyl group, an aryl group or a substituted aryl group; T 1 , T 2 and T 3 , which may be the same or different, represent a hydrogen atom, a C 3 -C 9 alkyl group, a C 3 -C 9 alkenyl group, or a C 3 -C 9 alkinyl group; T 4 represents a hydrogen atom, a C 1 -C 8 alkyl group, a C 3 -C 9 alkenyl group, a C 3 -C 9 alkinyl group or a phenyl group; in addition, T 3 and T 4 taken together with the nitrogen to which they are attached, may represent, a morpholino group, a pyrrolidino group, a piperidino group or a hexamethyleneimino group; and n represents an integer from 0 to 4; ##STR19## wherein R 11 represents an alkyl group of not more than 6 carbon atoms; R 12 represents an alkyl group of not more than 8 carbon atoms, a C 5 -C 7 cycloalkyl group, a benzyl group which may be substituted with a chlorine atom, a bromine atom and/or an alkyl group of not more than 4 carbon atoms, or a phenyl group which may be substituted with a chlorine atom, a bromine atom and/or an alkyl group of not more than 4 carbon atoms; X 1 and X 2 , which may be the same or different, represent an alkyl group of not more than 8 carbon atoms, an alkoxy group of not more than 8 carbon atoms, a fluorine atom, a chlorine atom or a bromine atom; m and n each represents 0, 1, 2 or 3; each X 1 of (X 1 )n, each X 2 of (X 2 )n or each X 3 of (X 3 )n can be the same or different; and X3 represents a chlorine atom or a bromine atom, in which at least one of X 3 in (X 3 ) 4 represents a bromine atom; ##STR20## wherein X represents a halogen atom; A represents a halogen atom, a nitro group, a C 1 -C 12 alkyl group, a C 1 -C 12 alkoxy group, a C 3 -C 10 cycloalkyl group, a cyano group or a hydroxy group; l represents 1 or 2; and m represents an integer from 0 to 5.