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T. A. Khattab and M. S. Abdelrahman
shift), thermochromic (temperature induced color shift) and electrochromic (electric current induced color shift) textiles. Other miscellaneous chromic compounds
and their related products is discussed. The chapter concludes the future trends in
developing chromic textile products.
2 Chromic Colorants
There is an extensive range of synthetic colorants that have been industrially presented for the coloration of various textile fibers. Conventional textile dyestuffs are
required to offer a constant color with high stability to light, washing, heat, perspiration and crocking. Variation in color of a certain fabric, usually known as color
fading due to poor colorfastness, upon exposure to washing, crocking, temperature,
perspiration or light is highly undesirable [11–13]. However, it was realized recently
that there are promising commercial niche applications for chromic colorants that
possess a distinctive color shift upon exposure to an external stimulus, particularly
when this color shift is reversible and can be controlled (Fig. 1). In general, chromic
colorants are those materials with the ability to radiate, replace or erase a color due
to stimulation by an external stimulus [14–21].
An extensive range of chromic colorants are currently well known and their fundamental chemical and physical properties have been explored [22–26]. List of different classes of chromic materials and the stimuli involved are summarized in Table 1.
Chromic compounds comprising photochromic, halochromic, thermochromic and/or
electrochromic properties have been the most extensively investigated smart colorants. The other chromic colorants listed are rather less recognized and either exhibit
limited commercial utilization or still an academic curiosity. Chromic colorants provide a considerable potential to offer particular functions in technical smart textiles, which have been designed to sense and response to the surrounding conditions
[27–30]. Depending on functional activity, smart clothing can be divided into three
different classes including passive, active and ultra smart textiles [31, 32]. Passive
smart clothing is only responsive to an external stimulus, such as temperature or
light, by changing color, such as presenting a warning signal. On the other hand,
active smart textiles respond to an external stimulus as a sensor or as an actuator
providing an electrical current from a central control unit, such as electronic textiles.
The ultra smart cloth can sense, react and adapt itself to an external stimulus. It is
mainly composed of a brain control unit. Ultra smart cloth is a combination between
Fig. 1 Reversible performance of chromic colorants
T. A. Khattab and M. S. Abdelrahman
shift), thermochromic (temperature induced color shift) and electrochromic (electric current induced color shift) textiles. Other miscellaneous chromic compounds
and their related products is discussed. The chapter concludes the future trends in
developing chromic textile products.
2 Chromic Colorants
There is an extensive range of synthetic colorants that have been industrially presented for the coloration of various textile fibers. Conventional textile dyestuffs are
required to offer a constant color with high stability to light, washing, heat, perspiration and crocking. Variation in color of a certain fabric, usually known as color
fading due to poor colorfastness, upon exposure to washing, crocking, temperature,
perspiration or light is highly undesirable [11–13]. However, it was realized recently
that there are promising commercial niche applications for chromic colorants that
possess a distinctive color shift upon exposure to an external stimulus, particularly
when this color shift is reversible and can be controlled (Fig. 1). In general, chromic
colorants are those materials with the ability to radiate, replace or erase a color due
to stimulation by an external stimulus [14–21].
An extensive range of chromic colorants are currently well known and their fundamental chemical and physical properties have been explored [22–26]. List of different classes of chromic materials and the stimuli involved are summarized in Table 1.
Chromic compounds comprising photochromic, halochromic, thermochromic and/or
electrochromic properties have been the most extensively investigated smart colorants. The other chromic colorants listed are rather less recognized and either exhibit
limited commercial utilization or still an academic curiosity. Chromic colorants provide a considerable potential to offer particular functions in technical smart textiles, which have been designed to sense and response to the surrounding conditions
[27–30]. Depending on functional activity, smart clothing can be divided into three
different classes including passive, active and ultra smart textiles [31, 32]. Passive
smart clothing is only responsive to an external stimulus, such as temperature or
light, by changing color, such as presenting a warning signal. On the other hand,
active smart textiles respond to an external stimulus as a sensor or as an actuator
providing an electrical current from a central control unit, such as electronic textiles.
The ultra smart cloth can sense, react and adapt itself to an external stimulus. It is
mainly composed of a brain control unit. Ultra smart cloth is a combination between
Fig. 1 Reversible performance of chromic colorants