The future of smart fabric

Numerous technologies employed in the realm of smart textiles have long existed, yet their integration into textiles may constitute a novel innovation worthy of patent protection. Despite challenges in developing smart textile technology, the potential for innovation in this field is substantial, and with rapid technological advancements, growth in this sector remains robust. Smart textiles, defined as intelligent fabrics incorporating smart components like sensors or electronics, offer enhanced functionality. This fusion of electronics and textiles produces intelligent and responsive materials in wearable forms (e.g., t-shirts, bras) or non-wearable applications (e.g., vehicle upholstery). These materials, embedded with sensors or electronics, can sense and react to environmental conditions, providing users with increased functionality, particularly in monitoring health and performance. Smart textiles find applications in healthcare, sports, military, and fashion industries.

Traditionally, fabric-based items prioritized comfort, fashion, or utility, without integrating electronic components or sensors. The challenge of integrating smart elements into textiles lies in maintaining comfort, as electronics or sensors may be bulky and uncomfortable. Functional textiles, with inbuilt functionality, closely align with smart textiles, resulting in textiles with desirable properties. The convergence of smart technology with the textile industry has spurred research and innovation, leading to increased intellectual property activity, with patented technology driving developments in the field.

Active research in smart textiles is widespread, ranging from universities to start-ups and multinational companies. For instance, Ulster University and Bioflex Yarns Ltd. collaborated on thermoregulating products, incorporating phase change materials into yarns, with potential applications in healthcare, particularly benefiting individuals with diabetes. In Canada, the University of Waterloo researchers developed a smart material that responds to both heat and electricity. This programmable fabric, made from polymer nano-composite fibers woven with recycled plastic and stainless steel, can change color and shape when stimulated. Canadian company Hexoskin, in collaboration with the Canadian Space Agency, created patented smart biometric clothing to monitor vital signs, with applications in healthcare, fitness, and space exploration. Their wearable respiratory inductance plethysmography technology is an example of patented innovation in the field.

General analysis

Integration with Wearable Technology:

Analysis: Integrating smart fabrics with wearable technology could lead to more user-friendly and convenient solutions. Users may prefer clothing that seamlessly incorporates health and fitness monitoring without the need for additional devices.
Case Study: Companies like Google and Levi's have collaborated on projects like Project Jacquard, creating connected garments with touch-sensitive fabric for gesture control.

Health Monitoring:

Analysis: The integration of health monitoring sensors in fabrics holds great potential for healthcare and sports industries. It could enable continuous and unobtrusive monitoring, leading to more proactive healthcare solutions.
Case Study: Hexoskin has developed smart clothing embedded with sensors to monitor metrics like heart rate, respiratory rate, and activity levels.

Adaptive Clothing:

Analysis: Fabrics that can adapt to environmental conditions or user preferences offer enhanced comfort and functionality. This could have applications in both daily wear and specialized garments for extreme conditions.
Case Study: Researchers at MIT have explored responsive fabrics that can change ventilation properties based on temperature and moisture levels.

Energy Harvesting:

Analysis: Energy harvesting technologies in smart fabrics could address the challenge of powering electronic components. This could lead to self-sustaining systems that reduce the need for external power sources.
Case Study: Wearable solar textiles, such as those developed by researchers at the Chalmers University of Technology, aim to generate electricity from solar cells integrated into fabrics.

Communication and Connectivity:

Analysis: Seamless communication within fabrics could enable data transfer, creating opportunities for interactive clothing and improved connectivity in the Internet of Things (IoT).
Case Study: The University of Manchester has developed conductive yarns for weaving electronic circuits into fabrics, enabling communication between devices.

Augmented Reality (AR) Integration:

Analysis: AR integration in smart fabrics could revolutionize the way we experience digital information, offering new possibilities for interactive clothing and immersive experiences.
Case Study: The Fashion Innovation Agency has collaborated with augmented reality companies to create AR-enhanced garments, blending digital and physical elements.

Environmental Sensing:

Analysis: Fabrics with environmental sensors could provide valuable data for users, contributing to personal well-being and environmental awareness.
Case Study: The Sensoree Mood Sweater uses sensors to detect the wearer's emotions, changing colors to reflect mood and promoting awareness of emotional states.

Customization and Personalization:

Analysis: Smart fabrics allowing customization could redefine personal style and preferences, offering users more control over their clothing's appearance and functionality.
Case Study: Adidas has explored 3D-printed, customizable sportswear, allowing users to personalize designs based on their preferences and performance needs.

Durability and Washability:

Analysis: Improving durability and washability is crucial for the practicality of smart fabrics in everyday use. Innovations in material science are essential to ensure longevity.
Case Study: Schoeller Textiles has developed fabrics with durable and washable electronic components, addressing concerns about the robustness of smart textiles in real-world usage.

Conductive materials play a crucial role in the creation of electrical components such as resistors, capacitors, inductors, and interconnects. To achieve flexibility in electronics, the reduction of dimensions is one approach, but utilizing flexible conductive materials enables the long-term adaptability of textiles. Conductive properties can be imparted to raw materials, yarns, or fabrics, and sensors, actuators, and power components can be crafted by layering conductive fabrics. The method chosen depends on factors like available equipment, desired conductivity, percolation threshold, and fabric rigidity requirements.

Conductivity can be introduced at various stages of textile production, including polymerization, fiber spinning, fabric construction, or post-processing through methods like coating or printing. Polymerizing conductive polymers or copolymers ensures high compatibility but can be costly and may not yield spinnable materials. During fiber spinning, conductive additives such as metals, carbon black, carbon powder, carbon whiskers, graphene, nanotubes, ionic liquids, and conductive polymers like polyaniline (PANI) and polyvinylidene difluoride (PVDF) can be incorporated to create electrically conductive composite fibers. However, the percolation threshold and desired conductivity impact fiber rigidity. Metallic materials generally have lower percolation thresholds and higher conductivity than non-metallic ones, influencing the choice of conductive materials.

Additives may increase fabric rigidity as they are less compliant than polymers. For fabric construction, wire-like conducting materials can be added during weaving or knitting as weft insertions, but they must withstand tension and bending without breaking. Metallic printing using nanoparticle inks and microdroplet printing during post-processing is an exciting option to add conductivity. Although post-processing is convenient, these materials may be more prone to issues such as cracking, delamination, and chipping due to poor adhesion and differences in material rigidity. In practice, the selection of the production step for adding conductivity often depends on expertise and available equipment rather than a strategic benefit.

Electronic textiles (e-textiles) have garnered significant interest for their diverse applications in the past decade. One prominent application is in smart textiles, facilitating interactions between humans and computers. Innovative approaches include the use of 3D printed elastomer networks, known as "optical lace," for sensing deformation, and the creation of tactile learning tools such as electronic embroidered books. These textiles can also enable sonification, providing auditory cues or translating non-audio data into sound. Patches embedded with triboelectric interaction structures enable wireless relay of signals, allowing control of machines through gestures.

Clothing serves as another versatile medium for electronic textiles. Gesture-controlled devices, such as glove-based interfaces, can decrease cognitive load during activities like driving. Highly conductive yarns woven into touch-sensitive sleeves demonstrate effective control of electronic devices. Standard fiber spinning processes produce bifunctional actuating/sensing fibers for haptic feedback and user interaction sensing. Various stimuli-responsive fibers, including thermally-drawn capacitor fibers and conducting/insulating fibers, showcase the flexibility and functionality of e-textiles. Overall, these applications demonstrate the broad potential of electronic textiles in enhancing human-machine interactions, sensing, and control across different domains.

E-textiles, or electronic textiles, involve incorporating multifunctional nanomaterials into traditional textiles to serve various purposes. These applications span human motion monitoring, healthcare functions like EMG and ECG, thermal heating, electromagnetic shielding, antimicrobial protection, self-cleaning, energy storage/harvesting, fire alarms, electronic displays, and color-changing capabilities. E-textiles address challenges associated with non-flexible and bulky wearable electronics by seamlessly integrating responsive electronic components into textiles. Wearable e-garments incorporate sensors, actuators, a flexible power supply, data processor, and external communication platform, all interconnected with conductive yarn/line, woven into the garment.

However, ensuring the durability and washability of e-textiles poses a challenge due to the potential degradation of nanomaterial coatings on textiles from factors like mechanical deformation, chemical exposure (sweat, blood, liquid, detergent), and daily wear and tear. The commercial success of e-textiles depends on overcoming these challenges to provide consistent performance and comfort in daily life. The washability of e-textiles is influenced by the geometry of textile interfaces, including 1D (fiber, yarn, filament), 2D (knitted, woven, nonwoven), and 3D (triaxial composite structure, braided). Developing washable and durable e-textiles with reliable substrates and architectures is crucial to meeting consumer demands for comfortable and functional wearable devices in various daily life scenarios.