Developer for thermal recording material and thermal recording materials

Abstract

The developer for a thermal recording material of the present invention comprises a condensed composition consisting of, of condensates represented by the formula (1): wherein R is a hydrogen atom, a hydroxyl group, a lower alkyl group having 1 to 5 carbon atoms, an alkoxyl group having 1 to 5 carbon atoms, an aryl group or an aralkyl group, R in the number of m may be the same or different and m is an integer of 0-3, X and Y are each a hydrogen atom, an alkyl group or an aryl group, provided that at least one of X an dY is an alkyl group or an aryl group, and n is an integer of 0-3, a condensate having two cores wherein n=0 or a condensed composition comprising a condensate having two cores wherein n=0 as a main component, and at least one kind of condensate of the formula wherein n=1-3 (3-5 core condensate). The developer for thermal recording materials of the present invention is applied to a heat-coloring layer of thermal recording materials, along with a basic dye (preferably further with a sensitizer). According to the present invention, a developer for thermal recording materials, which is capable of realizing a thermal recording material capable of affording high colored image density and superior in preservation stability of recorded images and non-image areas, while satisfying recent requirements for high sensitivity, can be obtained.

Description

technical field [0001] The present invention relates to a developer for a thermal recording material and a thermal recording material. More specifically, the present invention relates to a developer for a thermal recording material comprising a condensate or a condensate obtained by reacting a substituted phenol with a ketone compound or an aldehyde compound and a thermal recording material using the developer. combination. Background technique [0002] Generally, thermal recording materials are obtained by applying a coating liquid, which is obtained by grinding and dispersing a basic dye (colorless at ambient temperature), to a support such as paper, plastic film, etc., to form a thermally colored layer. Or light color) and organic developer to obtain their own fine particles, mix them and add binders, fillers, sensitizers, lubricants, other additives, etc. to the mixture. Provides a color record in which color develops by heating with a thermal head, thermal pen, laser,...

AI Technical Summary

Problems solved by technology

But conventional materials such as these are accompanied by problems such as low thermal response, insufficient color density obtained by high-speed recording, inconsistent color density, time course variation of color image density after recording, non-image parts during preservation (Background) discoloration, so-called blooming (blooming) deposition of white powder on the surface, decline in reprintability, etc.

However, although the sensitivity usually becomes high, there are problems depending on the kind and mixing ratio of the sensitizer (stabilizer), because the non-image area is faded (the color of the background is emphasized) and the preservation of the recorded image and non-image parts is stable Properties (heat resistance, moisture resistance, weather resistance) are not sufficiently improved, etc.

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