A drawing system according to an embodiment of the present disclosure includes a storage, an operation section, and a drawing section. The storage stores a characteristic function that derives output setting values of light sources on the basis of drawing coordinates, an absorbance correlation value, and gradation values in a leuco color space. The operation section derives the output setting values by inputting, to the characteristic function, the drawing coordinates, gradation values of leuco image data described in the leuco color space, and an absorbance correlation value obtained by measuring the recording medium. The drawing section includes the light sources, and controls output of the light sources on the basis of the output setting values derived by the operation section to thereby perform drawing on the recording medium.

A recording material and a recording sheet having better color-developing performance, storage stability, etc. A recording material which contains (A) at least one color former, (B) at least one compound selected from the group including compounds represented by the following formula (I), and (C) at least one compound selected from the group including compounds represented by the following formula (II) (wherein R.sup.1 to R.sup.3 each represent a halogen atom, a nitro group, a C.sub.1 to C.sub.6 alkyl group, a C.sub.1 to C.sub.6 alkoxy group, a C.sub.2 to C.sub.6 alkenyl group or a C.sub.1 to C.sub.6 haloalkyl group, n1 and n3 each independently represent any integer of 0 to 5, n2 represents any integer of 0 to 4, and X represents —SO.sub.2—O— or —O—SO.sub.2—). ##STR00001##

A thermosensitive recording medium having a thermosensitive coloring layer containing an electron-donating dye precursor, a radical photopolymerization initiator, and an electron-accepting compound with a radical polymerizable group, wherein the electron-accepting compound with a radical polymerizable group includes a compound A represented by the formula (1):

##STR00001##

There is disclosed a heat-sensitive recording material including an undercoat layer formed on one surface of a support and a heat-sensitive recording layer formed on the undercoat layer. The heat-sensitive recording layer contains a leuco dye and a coloring agent. The undercoat layer contains hollow particles and a binding resin. A maximum particle diameter (D100) of the hollow particles is 10 to 30 μm. A particle diameter (D50) of the hollow particles at cumulative 50 volume % is 4.0 to 15 μm. A ratio D100/D50 of the maximum particle diameter (D100) of the hollow particles to the particle diameter (D50) of the hollow particles at cumulative 50 volume % is 1.8 to 3.0. A volume percentage of the hollow particles having particle diameters of 2.0 μm or less is 1% or less.

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.

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.

The invention relates to a heat-sensitive recording material, comprising a carrier substrate and a heat-sensitive colour-forming layer, which contains at least one colour former and at least one phenol-free colour developer, characterised in that the at least one colour developer is the compound of formula (A), Ar(NH—CO—NH—CO—NH—Ar.sup.1).sub.n (A), wherein Ar is an unsubstituted or substituted phenyl or naphthyl group, Ar.sup.1 is an unsubstituted or substituted phenyl, naphthyl, pyridyl, thiazolyl or benzothiazolyl group, and n is 1 or 2.

Iodonium salt initiator and processing-free thermally sensitive plate precursor containing thereof, and processing-free thermally sensitive plate and use thereof, At least one of two para positions of two benzene rings of the iodonium salt initiator is an alkene group containing a carbon or nitrogen or oxygen atom and a double bond at an end. The alkene group can increase a steric hindrance of the iodonium salt, improves compatibility of the iodonium salt, the thermosensitive resin and the crosslinkable prepolymer, reduces the surface migration of the iodonium salt in the imaging layer and improves the initiation efficiency. During the laser imaging, a double bond contained in a residual end of the iodonium salt can perform a crosslinking reaction with the thermosensitive resin and the crosslinkable prepolymer, and thus reduces damage to the imaging layer caused by small molecules. At the same time, substituents can be arranged at four meta positions of the two benzene rings to increase the steric hindrance of the iodonium salt, and therefore, the surface migration of the iodonium salt in the imaging layer is further reduced, and the initiation efficiency is improved and the performance of the processing-free thermally sensitive plate is further improved.

##STR00001##

wherein, R.sup.1 to R.sup.10 each independently represent a hydrogen atom, a halogen atom, a nitro group, an amino group, an alkyl group, an alkoxy group, an aryl oxy group, an alkyl carbonyl oxy group, an aryl carbonyl oxy group, an alkyl carbonyl amino group, an aryl carbonyl amino group, an alkyl sulfonyl amino group, an aryl sulfonyl amino group, a monoalkyl amino group, a diakyl amino group, or an aryl amino group.

A heat-sensitive recording material including a substrate, a heat-sensitive recording layer which includes N-(4-methylphenylsulfonyl)-/V-(3-(4-methylphenylsulfonyloxy)pheny-purea and/or N42-(3-phenylureido)phenyl]benzol sulfonamide, and an intermediate layer which is arranged between the substrate and the heat-sensitive recording layer and which includes calcined aluminum silicate, and a method for producing a heat-sensitive recording material and to the use of calcined aluminum silicate in an intermediate layer of a heat-sensitive recording material.