Functional Dyes

A functional dye is a dye that absorbs or emits light,
or undergoes chemical or physical changes in response to external light, heat,
electricity, pressure, electric field or other forces.
Yamamoto Chemicals, which began operating as a manufacturer of dyes and pigments,
maintains an extensive range of organic synthesis technologies
and has expanded into various fields of functional dyes.


* Phthalocyanine is a beautiful blue-colored snowflake-like substance extracted from petroleum.

It is a blue organic pigment that has attracted attention due to its large spread of "π electrons" that exhibit optical and electronic functions.

This represents near-infrared resonance photosensitive dyes, which are the DNA of Yamamoto Chemicals.

Specific Wavelength Absorption Dyes

Specific Wavelength Absorption Dyes

Specific Wavelength Absorption Dyes are dyes that only absorb wavelengths across a specific range across the wide spectrum from ultraviolet to near-infrared. These includes dyes that absorb near-infrared light that is not visible to the naked eye, and dyes that only absorb specific colors. These are widely used in lenses for glasses and to give functions to displays.

Leuco dyes

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.

Dichroic Dyes

Dichroic Dyes

When a pigment is oriented, it can be made to appear colored from some directions and almost colorless from perpendicular directions. Dyes that produce this effect are known as dyes.

Polarizing films that use this property selectively absorb light traveling in one direction (i.e., polarized light) while absorbing almost none of the light traveling in a perpendicular direction (transmitting natural light and cutting reflected light).

In liquid crystal displays (LCDs), a dye is dissolved as a guest molecule in the liquid crystal and makes use of the fact that the dye is oriented in the same direction as the liquid crystal to produce a light shutter function without the use of polarizing film.

Various functional dyes

Various functional dyes

In addition to Specific Wavelength Absorption Dyes, leuco dyes and dyes, we also have a wide range of functional dyes.

We can also introduce to customers dyes that offer the specific properties they desire.

Contact Us

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

Telephone queries: [Tokyo Office]


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closed Saturdays, Sundays and public holidays

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