Abstract This chapter presents the subject and objectives of the book Color Changing Materials in the context of applied research and concept design. The implications of technical-scientific research on design theories and methods are described.
Smart Materials and Implications in Design
They are also able to detect the intensity of the specific stimulus and respond accordingly (Jiang and Feng 2010). The intelligence depends on the type of project and on the vision of the designer.
Classification of Chromogenic Materials
Because of all this, chromogenic materials offer a radical change in the way objects and media are designed, perceived and understood, and in the interaction with the real world that surrounds us: a more direct way, similar to natural and biological logic and human spirit. . The classical definition of solvatochromism is a change in the absorption spectra of chemical compounds caused by the surrounding medium.
Photochromic Materials
Some of these methods involve embedding the photochromic dye into the polymer matrix during the spinning phase of the synthetic fibers, such as polypropylene. In this way, the increased functionality of photochromic textiles compared to conventional ones can be seen as an added value in the textile product.
Thermochromic Materials
In the last two examples, thermochromic technology has been used to increase the performance of the products. Gel systems typically depend on a significant change in light scattering properties at the switching temperature.
Electrochromic Materials
- Electrochromic Devices
- Electronic Paper
- Electrochromic Devices for Windows
- Liquid Crystals
- LC Displays
- Liquid Crystal Devices for Windows
Thus, the director follows a spiral path, the height of which is inversely proportional to the mutual displacement of the molecules. The reflection and transmission of the device (screen or window) is directly related to the orientation of the LCs.
Chemochromic Materials
Gaschromic Materials
Hidden in the facade is a small electrolysis unit that produces hydrogen gas, and a miniature pump disperses the desired gas mixture into the cavity. The inner part of the pen, which is red, remains red, there is no oxygen in the atmosphere; she becomes frustrated. Fortunately, there is an oxygen supply in the raider and the red indicator inside the pen turns green.
Halochromic Materials
Instead, the coloring of halochrome non-woven material made from nanofibers can be obtained directly during fiber formation. The response of these sensors is fast due to the high porosity of the nanofiber substrate. The structure of the compounds can be regulated to optimize their reversibility (Tomasuolo and Raymo2010).
Hygro-Hydrochromic Materials
Several studies showed that halochrome dyes can be applied to conventional fabric using normal techniques and that the response of these sensors depends on the density of the fabric. For example, in the medical sector, halochrome bandages can be used for monitoring patients with burns. Hydrochromic materials have been used in the textile sector to achieve dynamic patterns on textiles.
Mechanochromic Materials
When stretched, the distance between the nanospheres increases, resulting in a color change to the blue region of the spectrum (Fig.2.26). Tampering or accidental damage to the closing area would be made visible through the color change of the film. A visible label on the packaging can be used to detect a pressure drop, which may be caused by a defective packaging or because it has been opened, to alert the customer to the condition of the product.
Biochromic Materials
One of the target markets of biochromic technology is the food industry, particularly in the detection of foodborne bacteria. Researchers at Berkeley National Laboratory developed biochromic sensors (also called colorimetric biosensors) for the detection of viruses, bacteria, parasites, neurotoxins, and other pathogens (Berkeley Lab2009; Charych et al. These biochromic sensors have potential applications as rapid test kits for influenza and other diseases, the detection of foodborne bacteria such as E.
Dynamic Color in Nature
The water penetrates the three-dimensional structure of the beetle's cuticle surface and changes its optical properties. Wiley, Chichester, West Sussex Lampert CM (1995) Chromogenic switchable glazing : towards the development of the smart. Project TeTRInno SmarTex (2007) State-of-the-art in the field of smart textiles and interactive fabrics.http://.
Liquid Crystals and their Use in Temperature Indicators
Therefore, the synthesis of liquid crystal molecules can be achieved by common procedures applied to the relevant chemical structure. As mentioned before, microencapsulation is the preferred method to protect the liquid crystal droplets during these processes. Alternatively, the black backing layer can be printed on the dried transparent plastic substrate containing liquid crystal ink (Sage2011; Hallcrest2012).
Leuco Dyes and their Incorporation into Polymers
Within the dye-developer-solvent system, leuco (colorless, from the Greek word leukos, meaning white) dyes play the role of electron-donating substances. The electron donated by the dye is accepted by the developer, which donates a proton to the leuco dye. The role of the solvent is to act as a host for the dye and developer, while also enabling the thermochromic reaction to be reversible with temperature.
Microencapsulation
A suitable method for incorporating leuco dyes into various polymers is to microencapsulate leuco dye developer solvent systems and use the microcapsules as pigments while forming the polymer in a plastic or liquid state. Another such system consists of crystal violet lactone (CVL) as a leuco dye, lauryl gallate as a color developer, and 1-tetradecanol or another long-chain alcohol as a solvent. Cooling to below 10 C, resulting in gelation of the liquid polymer (gelatin) on the leuco dye core.
Chromogenic Inks
Thermochromic leuco-dye inks have a shelf life of six months or more while stabilized photochromic inks can last for years before printing. After printing, thermochromic leuco dye ink can last for years if not exposed to too much UV light or temperatures above 140C. This ink is suitable for various printing processes such as offset, screen and flexographic printing.
Chromogenic Gels
The crystallinity of the array results in Bragg reflection (reflection of radiation from crystalline or periodic systems). The pre-gel solution was infiltrated into the cavities of the mold and polymerized to obtain the gel. The color of such a soft photonic crystal can be tuned as a result of the swelling and shrinking of the gel by various stimuli, including pH and temperature, Fig.
Printing and Coating with Chromogenic Inks and Dyes
The switching temperature can be set between 10 and 70C by varying the concentration of the components (Beck et al.1995). One or both sides of the substrate can be coated using processes such as stencil spin coating, counter roll coating, slot coating, gun spray, and dip coating. Chromogenic pigments can be added to the coating solution and applied to the surfaces of textiles or other substrates.
Chromogenic Textiles
Offset printing machines can be foil or coil type, single or multi-color, with a printing plate on one side or on both sides. For example, a polymer coating with thermochromic pigments can be applied to clothing as a visual indicator of thermal changes in the environment (Stylios2006). In addition, a chromogenic effect can be applied to any part of a textile product, depending on where the chromogenic fibers are applied during production.
Photochromic Eyeglass Lenses
Electrochromic Displays
Regardless of the electrochromic material used, a generic electrochromic display can be built using a five or more layer battery type design. The front of the screen is covered with a glass layer to contain the electrode and to provide high optical quality. The back of the screen may also have a glass layer that is either backed by a reflector, in the case of passive screens, or illuminated by a light source for active screens.
Smart Electrochromic Windows
In LCDs, in addition to the base layers discussed so far, polarizing films are used on both sides of the layered package to polarize the light. In addition, spacers of glass fibers or plastic balls are used to guarantee the desired thickness of the liquid crystal layer. Because liquid crystals flow easily, they must be sealed with suitable sealants (Collings and Hird1997).
Color and Design
Although the meaning of color depends on many factors, its emotional and physiological effects can be determined scientifically. Shoes that change color according to the season can create a niche market. Second, the rate of color change is typically much faster in the three media mentioned above, compared to today's chromogenic media.
Designing with Materials that Change Color
Thanks to such potentials, they have also been employed in the field of art, as for example in the work Heartby by the Japanese artist Kiyoyuki Kikutake. Textile design is one of the fields that has devoted the most energy to experimenting with smart materials in the last decade. In the field of textile design, various studies have focused on the use of thermochromic textiles for the development of visual communication devices, such as the work of Maggie Orth, one of the first creative and technical practitioners of e-textiles.
Theoretical and Methodological Considerations
Design Primario, Design and Perception,
In his book Designing Design, Hara defines his vision of the twenty-first century as an age of discovery. About some of designer Naoto Fukasawa's projects, Hara said: "Fukasawa's method is to study our subconscious behavior and design for it. Awakening the Five Senses (2007), Hara conducted research on perception and the ability of design to stimulate the creative awakening of human sensors.
Designing the Interaction
It studies the interaction between the user and the product to facilitate the use of the computer product and the interaction with the object. The experiential design approach, which is an extension of usability-focused design, is interested in the overall experience and satisfaction of the user while using a product or system with the aim of optimizing it. Today, experience design is one of the new focal points of product design research.
Technical and Economic Considerations
- Thermal Stability of Chromogenic Materials
- Light Stability
- Activation Temperature
- Switching Time
- Economics
Here, additional information related to the properties of some of the available chromogenic materials and technologies will be provided. Designers should select the appropriate chromogenic material taking into account both the process temperature and the application temperature of the product in question. Thermochromic leuco dyes are commercially grouped according to the temperature range of the chosen application.
Designing with Photochromic Materials
Sun-Reactive/Water-Reactive Dresses and Swimsuits
Most of the sun-reactive applications in these collections use screen-printed photochromic ink that changes from clear to purple in daylight. Some of the flowers and the bodice of the dress have been overlaid with white hydrochromic ink. On contact with water, this layer becomes transparent and reveals the color of the underlying print.
Drivewear Photochromic Lens by Younger Optics
As shown in the figure, parts of the triangles changed from light colors to a darker purple when exposed to sunlight. This product was not successful in the market because of the blue color produced in a darkened state, rather than the more neutral gray or brown colors people were used to. When bright sunlight hits the windshield, a smaller portion of the light can pass through the lenses, which are now copper-colored, reducing eye strain.
Designing with Thermochromic Materials
Thermochromic Brush by Corioliss
In Heat, Installation by Jürgen Mayer
Thus, the patterns became visible when heated, for example by the heat of the visitor's hand writing a comment, and disappeared as soon as the visitor's hand left the guestbook. Kiesler, who was also an architect, aimed to remove the boundaries of wall, floor, ceiling and merge them into an infinite, endless surface and space. The visitor, as he was at Kiesler's Blood Flames exhibition, becomes part of Fig.
LIE, Thermosensitive Bed Linens by Jürgen Mayer
Designing with Electrochromic Materials
Electrochromic Smart Glass by SmartGlass
In the "off" position, the molecules are randomly oriented, where most of the light is blocked and privacy is achieved. By activating the smart glass with a small current, the suspended rod-shaped particles become aligned, allowing light to pass through the panel. CERN wanted to keep the atmosphere and architectural beauty of the Globe intact while applying solar control.
Designing with Hydrochromic Materials
Solid Poetry
Designing with Biochromic Materials
TopCryo TM Time–Temperature Integrators
Developed by Nantes, France-based Cryolog, TopCryoTM is a time-temperature integrator designed as a simple label to explain the effect of time and temperature on heat- and time-sensitive products as they travel through the cold chain. An irreversible and easily measurable color change from green to red occurs on the label, indicating a break or abuse in the cold chain (Figure 5.18). The growth of microorganisms on the label causes a change in color from green to red, indicating that a similar process has occurred in the product inside the package (Potter.
Smart Systems
SymbiosisO, A Collection of Textile Interfaces
From the combination of SymbiosisCandSymbiosisScamePlay Me. Fig.5.25), the first product of the series made in collaboration with K–O–I Design. The last installation of the collection is SymbiosisO:voxel (Fig.5.26) realized in collaboration with the artist Alex Dodge and presented at Tribeca Issey Miyake in 2012. In the overseas state of the intelligent system, the surface has an intense blue color; in theonstate, a white graphic pattern appears (an edge showing a division within the voxels, describing a cube seen in perspective view).
Fabrication Bag by Hanna Landin and Linda Worbin
In this project, a thermochromic ink was applied to a cotton textile in combination with a conductive yarn on the reverse side to control the color change of the thermochromic print. The Fabrication Bag concept (Figure 5.29) is intended as an accessory for mobile phones that replaces sound and vibration signals by changing colors in textile patterns on the outside and inside of the bag. The bag's textile contains several layers of thermochromic ink printed in dots that are activated by heat patches underneath (Figure 5.31).
Pollution Monitoring Fashion by Sue Ngo
This color can be electrically driven to display multiple gray levels of the same base color. Steel wires used as conductors are sewn to the back of the fabric, placed every 5 mm in the direction of the weft. When the thermochromic ink becomes transparent, the shape of the pattern changes (interference of the shape with the color palette).
