Leuco Dyes

Leuco dyes develop color when they come into contact with acid under the action of heat or pressure.
In addition to being used as a coloring material in thermosensitive recording paper (facsimile paper)
and pressure-sensitive copy paper (non-carbon paper),
leuco dyes are also used in heat color development transparent films and heat sensitive paints.

Thermal and pressure-sensitive dyes

Leuco dye, which develops color when it comes into contact with a developer acid, is used.

It is used for thermal paper and pressure-sensitive paper, which produce color through the following actions.

Thermal paper:
When heat is applied, the dye and developer melt to produce color.

Pressure-sensitive paper:
When pressure is applied to capsules that contain dye, the capsules rupture and cause the dye to come into contact with the developer, producing color.

Dyes for heat sensitive materials

Heat-sensitive materials have properties that utilize a reversible reaction between a leuco dye and color developer to change color (between colored and colorless) due to heat.

As the color change is reversible when a specific temperature range is reached, it is used to indicate proper temperature or detect temperature in foods and beverages, and to change the color of toys and other items.

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For consultations or queries regarding
Yamamoto Chemicals and its products,
feel free to contact us via telephone
or the email inquiry form.

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