A recording material and a recording sheet having excellent color-developing performance and storage stability and particularly having excellent heat-resistance of background. The recording material contains a color former (A), a compound represented by formula (I) (B), and a compound represented by formula (II) (C).

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A color-forming composition is useful to provide a printout image in an imaged lithographic printing plate precursor. This color-forming composition includes (a) an acid generator; (b) a tetraaryl borate; (c) an acid-sensitive dye precursor; and (d) a compound having the following Structure (I):

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wherein n is 1, 2, 3, or 4; R independently represents a monovalent substituent or the atoms necessary to form a fused ring if n is at least 2, and at least one R substituent is an electron-withdrawing group. The color-forming composition is included within a negative-working radiation-sensitive imageable layer along with a free radically polymerizable component and a radiation absorber such as an infrared radiation absorber.

According to one embodiment, a recording medium is a recording medium in a card form. The recording medium includes a substrate, and a color development layer laminated on the substrate, and provided with a line for security that extends along a lamination surface of the substrate from an end face of the recording medium, such that presence or absence of the line for security is optically identifiable at the end face. It is thus provided a recording medium that can easily prevent falsification with a simple structure, and allows authenticity determination to be performed relatively easily.

An object of the present invention is to provide a recording material or a recording sheet using, as a color-developing agent, a non-phenol-based compound good in color developing performance and the like. A compound represented by the following formula (I) is used as the color-developing agent:

##STR00001##

(wherein X represents CH.sub.2 or the like; R.sup.1 to R.sup.3 each independently represent a hydrogen atom, a halogen atom or the like; n1 and n3 each independently represent any integer of 1 to 5; two groups represented by R.sup.3 adjacent to each other on a benzene ring optionally bond to each other to form an optionally substituted 6-membered ring; and n2 represents any integer of 1 to 4).

Dual functionality recording media are disclosed. The recording media or materials can impart information both by direct thermal printing, and by being receptive to a modified inkjet printing technology known in the art as Memjet printing, which combines microelectromechanical systems (MEMS) and inkjet technology. The recording materials include a base substrate to which several coatings are applied. The coatings are selected to provide both direct thermal functionality and receptivity to Memjet-type dye-based inks as applied in Memjet-type printing systems. Heat-sensitive recording capability is provided by a leuco dye/acidic developer combination. Receptivity to Memjet-type dye-based printing is provided by a topcoat of suitable composition. The present inventors recognized that Memjet-type inks printed onto the topcoat suffer from a graying problem, but the problem is solved by appropriate selection of the leuco dye/acidic developer combination.

The laminate includes: a base material; an intermediate layer provided on the base material and having an accommodation part; a recording medium provided in the accommodation part; and an overlay layer provided on the intermediate layer. The accommodation part is provided in a part of a plane of the intermediate layer, and the accommodation part is a through hole penetrating in the thickness direction of the intermediate layer or a recess recessed in the thickness direction of the intermediate layer. The recording medium includes a color development layer containing: a coloring compound having an electron donating property; a developer having an electron accepting property; and a matrix resin. The base material, the intermediate layer, and the overlay layer contain the same type of resin material. The base material and the intermediate layer are bonded to each other by fusion, and the intermediate layer and the overlay layer are bonded to each other by fusion.

As a thermosensitive recording medium utilizes a coloring reaction between a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent, a thermosensitive recording medium using an environment-friendly color developing agent is provided. Provided is a thermosensitive recording medium having a thermosensitive recording layer comprising a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent on a substrate, wherein the thermosensitive recording layer comprises a gluconolactone as the electron accepting color developing agent.

A reversible recording medium of an embodiment of the present disclosure includes a support base and a recording layer. The recording layer is provided on the support base and reversibly changes between a recorded state and a deleted state. A chroma difference C* between the support base and the recording layer satisfies the relational expression (1) where an absorption spectrum in a visible region of the recording layer in the deleted state and an absorption spectrum in a visible region of the support base are each denoted by L*a*b*.

A reversible recording medium of an embodiment of the disclosure includes a support base, and a recording layer provided on the support base and reversibly changing between a recorded state and a deleted state. The recording layer includes a photothermal conversion material including one or more of a compound having a phthalocyanine skeleton, a compound having a squarylium skeleton, a compound having a cyanine skeleton including, in a molecule, one or both of a counter ion of SbF.sub.6, PF.sub.6, BF.sub.4, ClO.sub.4, CF.sub.3SO.sub.3 and (CF.sub.3SO.sub.3).sub.2N and a methine chain containing a five-membered ring or a six-membered ring, and an inorganic compound; a coloring compound having an electron-donating property; and a color developing/quenching agent having an electron-accepting property and including at least one salicylic acid compound represented by the general formula (1) and including a linear hydrocarbon group having 25 to 34 carbon atoms via a linking group containing an amide moiety.

Disclosed is a heat-sensitive recording material comprising an undercoat layer and a heat-sensitive recording layer formed in this order on a support, the undercoat layer containing hollow plastic particles and a binder, the heat-sensitive recording layer containing a leuco dye and a developer, and the heat-sensitive recording material having an elastic modulus of 200 N/mm.sup.2 or less as measured by a nanoindentation method.