Revealable substrates and methods include an opacifying layer having a plurality of irregular and/or odd-shaped opaque polymer particles defining voids therebetween. At least part of the opacifying layer may be induced to become transparent, for example, by collapsing at least some of the voids to reduce or eliminate internal reflection of light in the opacifying layer. Upon rendering transparent the portion(s) of the opacifying layer, a color material (e.g., ink) disposed underneath the opacifying layer is revealed and/or viewable therethrough.

Revealable substrates and methods include an opacifying layer having a plurality of irregular and/or odd-shaped opaque polymer particles defining voids therebetween. At least part of the opacifying layer may be induced to become transparent, for example, by collapsing at least some of the voids to reduce or eliminate internal reflection of light in the opacifying layer. Upon rendering transparent the portion(s) of the opacifying layer, a color material (e.g., ink) disposed underneath the opacifying layer is revealed and/or viewable therethrough.

A thermosensitive recording medium 100 includes a support 50, and a first thermosensitive coloring layer 10, a first intermediate layer 15, and a second thermosensitive coloring layer 20 disposed on the support 50 in descending order of distance from the support 50. The first thermosensitive coloring layer 10 and the second thermosensitive coloring layer 20 each contain an electron-donating dye precursor, an electron-accepting compound, a radical-polymerizable compound, and a photoradical polymerization initiator, and the first intermediate layer 15 contains a UV absorber.

A thermosensitive recording medium 100 includes a support 50, and a first thermosensitive coloring layer 10, a first intermediate layer 15, and a second thermosensitive coloring layer 20 disposed on the support 50 in descending order of distance from the support 50. The first thermosensitive coloring layer 10 and the second thermosensitive coloring layer 20 each contain an electron-donating dye precursor, an electron-accepting compound, a radical-polymerizable compound, and a photoradical polymerization initiator, and the first intermediate layer 15 contains a UV absorber.

In a drawing method according to an embodiment of the present disclosure, when performing drawing on a thermal recording medium that includes, above a recording layer, a light-transmitting member having an uneven shape in a plane, an optical compensator having one surface and another surface is provided on the light-transmitting member to cause the one surface and the light-transmitting member to face each other, and the thermal recording medium is irradiated with a laser beam via the optical compensator. The one surface of the optical compensator has a shape that fits the uneven shape of the light-transmitting member, and the other surface is flat and opposed to the one surface.

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.

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 method (1) for preparing a laser marking system (100) to create a colored laser mark on a specimen comprising the following steps: a) Providing a laser marking system (100) and a specimen (105) comprising a surface layer (105a), wherein the laser marking system comprises a preset number of laser parameters (12); b) Performing an exploration of a first gamut (2) specified by the laser marking system (100) and the specimen (105) comprising a surface layer (105a) including the following steps: aa) Creating (3) a design space (10) with a preset number of design points (11), wherein each design point (11) represents a combination of the preset number of laser parameters (12); bb) Performing (4) a marking of a sample on the specimen (105) for each design point (11); cc) Measuring (5) the sample using at least one detection device (106) and deter-mine for each design point a performance point (14), wherein the measured performance points (14) define a performance space (13); dd) Evaluating (6) the performance space (13) with regard to preset performance criteria using an evaluation device (107), wherein a Pareto front is determined comprising a subset of performance points; ee) Generating (7) an offspring design space (10a) with offspring design points (11a); ff) Creating (8) a first gamut (2) using the subset of performance points forming the Pareto front; wherein the steps bb) to dd) are iterated (9) for a preset iteration number, wherein in each iteration (9) the offspring design space (10a) of the previous iteration is used in step bb), wherein in each iteration the measured performance space is combined (15) with the performance space of the previous iteration (9) such that in step dd) the combined performance space (13a) is used.

A method (1) for preparing a laser marking system (100) to create a colored laser mark on a specimen comprising the following steps: a) Providing a laser marking system (100) and a specimen (105) comprising a surface layer (105a), wherein the laser marking system comprises a preset number of laser parameters (12); b) Performing an exploration of a first gamut (2) specified by the laser marking system (100) and the specimen (105) comprising a surface layer (105a) including the following steps: aa) Creating (3) a design space (10) with a preset number of design points (11), wherein each design point (11) represents a combination of the preset number of laser parameters (12); bb) Performing (4) a marking of a sample on the specimen (105) for each design point (11); cc) Measuring (5) the sample using at least one detection device (106) and deter-mine for each design point a performance point (14), wherein the measured performance points (14) define a performance space (13); dd) Evaluating (6) the performance space (13) with regard to preset performance criteria using an evaluation device (107), wherein a Pareto front is determined comprising a subset of performance points; ee) Generating (7) an offspring design space (10a) with offspring design points (11a); ff) Creating (8) a first gamut (2) using the subset of performance points forming the Pareto front; wherein the steps bb) to dd) are iterated (9) for a preset iteration number, wherein in each iteration (9) the offspring design space (10a) of the previous iteration is used in step bb), wherein in each iteration the measured performance space is combined (15) with the performance space of the previous iteration (9) such that in step dd) the combined performance space (13a) is used.

A method for marking a printed object is disclosed. For example, the method includes printing a three-dimensional (3D) object via a fused filament fabrication (FFF) printer, receiving a desired color marking to be marked on a surface of the 3D object, and controlling a point energy source to emit energy on a thermal treatment layer of the 3D object in accordance with the desired color marking.