A fiber assembly according to one embodiment of the present disclosure includes a fiber. The fiber includes a core part that contains a coloring compound, a photothermal conversion material, and a color developer/reducer, and a sheath part that covers the core part and has a heat-insulating property.

A composition includes a capsules having an improved solvent and heat resistance. The capsules are prepared via interfacial polymerization between a polyisocyanate including at least one substituted or unsubstituted arylene or heterearyl group and a compound including an active hydrogen. The capsules include a leuco dye and may be used in laser markable compositions.

A composition includes a capsules having an improved solvent and heat resistance. The capsules are prepared via interfacial polymerization between a polyisocyanate including at least one substituted or unsubstituted arylene or heterearyl group and a compound including an active hydrogen. The capsules include a leuco dye and may be used in laser markable compositions.

A composition includes a capsules having an improved solvent and heat resistance. The capsules are prepared via interfacial polymerization between a polyisocyanate and a polyhydrazide. The capsules include a leuco dye and may be used in laser markable compositions.

A composition includes a capsules having an improved solvent and heat resistance. The capsules are prepared via interfacial polymerization between a polyisocyanate and a polyhydrazide. The capsules include a leuco dye and may be used in laser markable compositions.

An erasing unit according to an embodiment of the present disclosure is a unit that performs erasing of information written on a reversible recording medium. This erasing unit includes: a light source section including one or a plurality of laser devices; and a controller that controls the light source section to cause the light source section to emit a smaller number of laser light beams having emission wavelengths than the number of the recording layers included in the reversible recording medium.

A three-dimensional structure according to an embodiment of the present disclosure includes: a plurality of resin layers including a light curable resin, the light curable resin including a coloring compound, a color developing-reducing agent, and a photothermal conversion agent, the plurality of resin layers being stacked, the color developing-reducing agent having an average particle diameter of 10 m or more and 100 m or less.

The present invention relates to method of manufacturing a tamper-proof medium for thermal printing, wherein a liquid treatment composition comprising at least one acid is deposited on a substrate which comprises a thermochromic coating layer comprising at least one halochromic leuco dye.

The present invention relates to method of manufacturing a tamper-proof medium for thermal printing, wherein a liquid treatment composition comprising at least one acid is deposited on a substrate which comprises a thermochromic coating layer comprising at least one halochromic leuco dye.

A three-dimensional structure according to an embodiment of the present disclosure includes a plurality of resin layers including a light curable resin, a coloring compound, a color developing-reducing agent, and a photothermal conversion agent, the plurality of resin layers being stacked.