A laser markable composition includes (a) an aqueous medium; (b) a leuco dye; (c) an optothermal converting agent; and (d) a color developing agent, characterized in that the color developing agent is a polymer particle capable of forming an acid upon exposure to heat.

A thermosensitive recording material including a support and a thermosensitive coloring layer provided on the support, in which the thermosensitive coloring layer contains (A) a coloring substance, (B) a kraft lignin in which a content of dimethyl disulfide is 2.5 ppm or less and (C) a specific developer.

A laser markable composition includes (a) an aqueous medium; (b) capsules composed of a polymeric shell surrounding a core; (c) a colour developing agent or colour developing agent precursor; and (d) an optothermal converting agent; characterized in that the core of the capsule contains a leuco dye.

A laser markable composition includes (a) an aqueous medium; (b) a leuco dye; (c) an optothermal converting agent; and (d) a colour developing agent, characterized in that the colour developing agent is a polymer particle capable of forming an acid upon exposure to heat.

A heat-sensitive recording material including a web-shaped substrate having a front side and an opposite reverse side, and at least one heat-sensitive recording layer on either or both of the sides of the web-shaped substrate. The heat-sensitive recording layer contains a color acceptor having a combination at least consisting of one, two, three or more than three color acceptor (compounds) of formula (1) ##STR00001## where R is alkyl, and of at least one secondary color acceptor comprising lactic acid oligomers conforming to formula (3) ##STR00002##

Color change compositions that transition from a first to second color state upon application of an applied stimulus are provided. Also provided are substrates having the compositions on a surface thereof, as well as methods of making and using the compositions.

The present invention provides a heat-sensitive recording material having a high recording density, excellent plasticizer resistance in recorded portions, and excellent resistance to thermal background fogging in high-temperature environments. The heat-sensitive recording material includes a heat-sensitive recording layer containing a specific sulfonamide compound.

A composition for forming a visually discernible color, the use of this composition for producing a heat-sensitive recording material, the corresponding heat-sensitive recording material includes a substrate and this composition, and a process for producing the heat-sensitive recording material.

A heat-sensitive recording material including a web-shaped substrate having a front side and an opposite reverse side, and at least one heat-sensitive recording layer on either or both of the sides of the web-shaped substrate.

The heat-sensitive recording layer contains a color acceptor having a combination at least consisting of one, two, three or more than three color acceptor (compounds) of formula (1)

##STR00001## where R is alkyl, and of at least one secondary color acceptor comprising lactic acid oligomers conforming to formula (3)

##STR00002##

This disclosure provides laser markable polymerizable resin compositions comprising infrared absorbing marking additives to achieve improved laser markability of 3-D printed objects obtained from these polymerizable resin composition, and methods for marking the cured resin compositions using an infrared laser.