**1. Introduction**

Textiles, with the basic characteristics of clothing, protection, and esthetics, are the indispensable part of our lives, but in recent years with the development of technology and the variation of requirements, the demand to smart materials and intelligent textiles grows increasingly all over the world. In other words, technology has also taken control of textile industry. Smart textiles have superior performance and functionalities for the applications ranging from simple to more complicated uses such as military, healthcare, sportswear, etc. Smart or intelligent textiles can also be called as the next-generation textiles.

Many classifications related to smart textiles are available in the literature. In this chapter, the classifications based on the esthetic and performance functions are mentioned as two categories. Esthetic smart textiles use the technology for fashion design, because of their ability to light up and change color. Light-emitting clothes and luminous dresses are the typical and commercial examples for esthetic smart textiles. As for the performance, smart textiles are classified into three categories as passive smart textiles, active smart textiles, and ultra smart textiles.

Passive smart textiles can only sense the environment, as they are just sensors. UV protecting clothing, conductive fibers, plasma-treated clothing, and waterproof fabrics are the typical examples of passive smart textiles. Active smart textiles can sense the stimuli from the environment and also react to them; besides the sensor function, they also have an actuator function. Phase change materials, shape memory materials, and heat sensitive dyes are active smart textile applications.


#### **Table 1.**

*Classification of smart textiles.*

Ultra smart textiles take a step further. Ultra smart textiles are materials that sense, react, monitor, and adopt themselves according to the stimuli or environmental conditions, such as thermal, mechanical, chemical, magnetic, or other sources. An ultra smart or intelligent textile essentially consists of a unit which works like a brain, with cognition, reasoning, and activating capacities. For instance, spacesuits, musical jackets, and wearable computers are ultra smart materials [1, 2] (**Table 1**).

In the mid-1970s, with the development of personal computers, a technological explosion was recorded in all the areas of human activity for any purposes. In the early 1990s, the benefits of smart textiles became apparent. Many researchers have studied on smart materials and textiles. Chan Vili studied the use of shape memory materials in developing high performance smart textiles, taking into consideration the ways for enhancing the esthetics of woven interior textiles. Dunne et al. provided an overview on textile integration strategies and component attachments. Choi and Jiang presented a system intended for cardiorespiratory measurement to monitor sleep condition. Mattmann et al. analyzed a yarn sensor that is nearly hysteresis-free while measuring elongation along body parts, for example, the back. Paradiso et al. presented a smart garment that can be used as wearable healthcare system. Cho et al. compared different conductive textiles and their performance for measuring joint angles.

The market for smart textile is growing with a high potential globally. The rise in demand for smart textile products is causing the existing market to expand, leading the way to new players to enter the smart textile market. In the emerging economies, the market share of smart textile consumed relative to conventional textile products is increasing. The global smart textile market size is expected to reach \$5369 million by 2022 from \$943 million in 2015, with a CAGR of 28.4% from 2016 to 2022. The global smart textile market is thriving and witnessing significant growth owing to the numerous applications in various industries.

### **2. Functions of smart textiles**

Smart textiles are smart systems that can both perceive or communicate the environmental conditions and can detect and process the wearer's condition. They can use electrical, heat, mechanical, chemical, magnetic, and other detection systems to detect them. Smart garments are separated from wearable computing systems by revealing the importance of the garment on which they are integrated. Wearable computing systems are formed by the traditional systems being attached to the garment in some way. The equipment used is placed in non-textile ways without being integrated. Although some electronic materials have been reduced to be used in garments, the actual smart garments should use materials made entirely by textile production. The electronic materials to be placed must not impair the comfort of the standard textile material garment. Therefore, providing this combination is vital for wearability in smart garment and textile manufacturing. It is clear that smart textiles are simple computer systems and have five functions basically

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**2.1 Sensors**

**Figure 1.**

*Functions of smart textiles.*

example, photoresistors.

piezoelectric materials.

or piezoelectric phenomena.

*Smart E-Textile Materials*

*DOI: http://dx.doi.org/10.5772/intechopen.92439*

as sensors, data processing, actuators, storage, and communication (**Figure 1**). But it must be compatible with the function of clothing such as comfort, durability,

Sensors are the components that transform one type of signal into another type of signal. There are already systems in the textiles that measure heart, breath rate, temperature, movement, and moisture, but these systems work with the installation of traditional sensors in textiles. At the present stage of intelligent textiles, the sensors are produced from real textile material, and the heart, breath, and movement sensitive sensors are already produced with satisfactory results. There are also different materials and structures that have the capacity of transforming signals:

• **Thermal sensors:** a thermal sensor detects thermal change, for example, a thermistor that changes resistance due to thermal change. Another example is the stimuli-responsive hydrogels that swell in response to a thermal change.

• **Light sensors:** these sensors that convert light energy into voltage output, for

• **Sound sensors:** these converts sound into an electrical signal, for example,

• **Humidity sensors:** these sensors measure absolute or relative humidity. An example that can be interesting for textile use is the capacitive device that

• **Pressure sensors:** these sensors convert pressure to an electrical signal. A pressure sensor can be based on simple operations such as opening or closing a circuit. But they may also be based on more sophisticated forms like capacitive

changes dielectric properties with the absorption of moisture.

resistant to regular textile maintenance processes, and so on [1, 2].

*Advanced Functional Materials*

Passive smart textiles **√**

*Classification of smart textiles.*

**Table 1.**

Active smart textiles **√ √**

Ultra smart textiles **√ √ √**

measuring joint angles.

**2. Functions of smart textiles**

Ultra smart textiles take a step further. Ultra smart textiles are materials that sense, react, monitor, and adopt themselves according to the stimuli or environmental conditions, such as thermal, mechanical, chemical, magnetic, or other sources. An ultra smart or intelligent textile essentially consists of a unit which works like a brain, with cognition, reasoning, and activating capacities. For instance, spacesuits, musical jackets, and wearable computers are ultra smart materials [1, 2] (**Table 1**). In the mid-1970s, with the development of personal computers, a technological explosion was recorded in all the areas of human activity for any purposes. In the early 1990s, the benefits of smart textiles became apparent. Many researchers have studied on smart materials and textiles. Chan Vili studied the use of shape memory materials in developing high performance smart textiles, taking into consideration the ways for enhancing the esthetics of woven interior textiles. Dunne et al. provided an overview on textile integration strategies and component attachments. Choi and Jiang presented a system intended for cardiorespiratory measurement to monitor sleep condition. Mattmann et al. analyzed a yarn sensor that is nearly hysteresis-free while measuring elongation along body parts, for example, the back. Paradiso et al. presented a smart garment that can be used as wearable healthcare system. Cho et al. compared different conductive textiles and their performance for

**Sensing external conditions Reacting Responding and adopting**

The market for smart textile is growing with a high potential globally. The rise in demand for smart textile products is causing the existing market to expand, leading the way to new players to enter the smart textile market. In the emerging economies, the market share of smart textile consumed relative to conventional textile products is increasing. The global smart textile market size is expected to reach \$5369 million by 2022 from \$943 million in 2015, with a CAGR of 28.4% from 2016 to 2022. The global smart textile market is thriving and witnessing significant

Smart textiles are smart systems that can both perceive or communicate the environmental conditions and can detect and process the wearer's condition. They can use electrical, heat, mechanical, chemical, magnetic, and other detection systems to detect them. Smart garments are separated from wearable computing systems by revealing the importance of the garment on which they are integrated. Wearable computing systems are formed by the traditional systems being attached to the garment in some way. The equipment used is placed in non-textile ways without being integrated. Although some electronic materials have been reduced to be used in garments, the actual smart garments should use materials made entirely by textile production. The electronic materials to be placed must not impair the comfort of the standard textile material garment. Therefore, providing this combination is vital for wearability in smart garment and textile manufacturing. It is clear that smart textiles are simple computer systems and have five functions basically

growth owing to the numerous applications in various industries.

**244**

as sensors, data processing, actuators, storage, and communication (**Figure 1**). But it must be compatible with the function of clothing such as comfort, durability, resistant to regular textile maintenance processes, and so on [1, 2].
