26 Build and Mobile Textiles

S. Amsamani

BUILD TECH

1.1 INTRODUCTION

Building especially houses for shelter from climate conditions and for protection from animals has been a part and parcel of mankind since Stone Age. The buildings which were cave and huts of straws have changes into multi- store buildings and high tech houses of concrete, wood, stone, metal and textiles. Textiles find their way into building sector too. They are utilised in numerous ways during building construction. The thriving construction activities and requirement for novel materials for specific end uses has boosted the demand for build tech supplies. In this era of e-commerce, delivering things through road transport, created more demand for HDPE tarpaulin. The rise in number of hotels and outdoor parties has created the need for awnings and canopies. During 2016-17, India’s buildtech segment is expecting a growth rate of 17% about US$ 541 Million, as per estimates, Ministry of Textiles, Government of India.

1.2 OBJECTIVES

At the end of the session the learner will be able to

•  Gain knowledge about the types of textiles and their function in build tech sector
•  Distinguish the role of build tech materials in construction activities

1.3 DEFINITION

The textiles or composite materials used during the construction of temporary and permanent buildings and structures like hoardings, architectural membranes, tarpaulins, scaffolding nets, signages, awnings, etc. are classified as buildtech segment. In other words buildtech could be described as any fiber, yarn or fabric used during the process of civil work to speed up the process of construction or to enhance the building itself. Buildtech includes items from course jute bags to very fine glass sheets.

1.4 TYPES OF BUILDTECH PRODUCTS

1.4.1 Architectural membranes

Architectural membranes are used for the construction of semi-permanent and permanent structures such as display halls, walkways, pool surrounds, sports halls, stadiums, car park covers, hotels, storage centers for military and industrial supplies, airports, cafes, greenhouses, exhibitions, outdoor entertainment areas, to provide protection from harsh UV rays, glare, heat, rain and wind. Titanium dioxide coated membranes are mostly used in high architectural designed buildings. Fiber glass membranes with good tensile strength are used in the exteriors areas. They are very strong and energy efficient products that gives flexibility to architects and designers. The characteristics of the material used as build tech need to be fire retardant, resistant to wind and air, water proof and deformation under tension. Some time these fabrics are also treated with chemicals to resistant microbial attack, sunlight, acid, mechanical damage and abrasion. Depending upon the application and location architectural membranes is sub divided as Clear-span, Tension and Air Structures. Common materials used for Architectural Membranes are PVC coated polyester, Acrylic top coat, PVDF/PVC Top-Coating, Polyvinyl Fluoride Top-Coating, PTFE (Poly tetra Fluoro Ethylene) and coated Glass.

Fabric1.4.2 Hoardings and Signages

Translucent flexible textile substrate called flexible-face sign fabric (flex) is used to make hoardings and signages. Flex is used as a substitute to rigid-faced substrates like plastic, acrylic and polycarbonates. It is light weight and easy to handle, transport and store. It is flexible in taking graphics and is amenable to painting, screen printing and inkjet printing. With flex, it is possible to make large seamless signages and it is constructed in such a way to withstand wind at the speed of 110 to 140 miles per hour. Flex is also used for trade show displays, light boxes, exhibits and advertising.

Flex is fabricated by using high tenacity polyester filament with 250 to 500 denier yarn warp knitted and coated with PVC on fabric and surface is treated with lacquer. The properties of flex fabric are printability, heat sealability, light transmission, ultra violet resistance, mildew  resistance and anti-wicking. Nearly 80-90% of the flex is imported from China. Flex is manufactured by coating the base fabric either by dip or knife roll method with PVC emulsion followed by drying and curing.

1.4.3 Tarpaulins

A tarp or tarpaulin is a large sheet of water resistant or waterproof, strong and flexible, material. Tarpaulin is generally used in trucks and other automobiles for transportation protect sheds from rain water, in storage godowns, construction sites, boats, temporary storages, snowmobiles, grain storage, and tents. It is also used in agricultural sector, construction and marine works. Conventionally tarpaulins are manufactured with cotton, canvas and jute. With the growth in technology and change in climatic conditions and methods of storage, means of transport nylon polyester, plastic fabrics are largely used today. Tarpaulins are grouped as Cotton canvas Tarpaulins and HDPE/PP/Nylon Tarpaulins. Irrespective of the raw material used most of the tarpaulins are coated with PVC. The available GSM of cotton canvas is from 380 to 500 GSM. Polyester fabrics of 102 to 107 GSM and poly vinyl of 610 to 678 GSM are also used. Polyethylene tarpaulin is also known as laminated tarpaulin. They are comparatively cheaper than cotton canvas tarpaulins.

1.4.4Awnings and Canopies

A secondary covering material attached to the exterior wall of a building is called an awning. The position of awnings on a building are at above the window, door, or above the area along a side walk. Restaurants use awnings to cover outdoor area for parties or reception. The main roles of awning are to provide protection from sunlight, UV radiation, snow, rain, and break steep winds and to impart decoration and identification. Their advantages are high tear strength, good breaking strength, weather protection, good drape and look. These are made up of woven canvas, acrylic, polyester or cotton yarn, or polyester fabric laminated with vinyl. They are stretched tightly over light structure aluminum, iron or steel and sometimes even wood. The raw materials used are 50 to 150 gsm woven or warp knitted fabric made of filament yarn coated with water based PU emulsion, emulsion grade PVC, plasticizer, fillers like China clay, CaCO3, and  addictives such as colour pigments and stabilizers. The rise in the hotel industries and real estate business has boosted the demand for awnings and canopies.

1.4.5 Floor and Wall Coverings

Textiles had been a part of floor and wall coverings since the invention of buildings. Textiles were used to increase comfort and look. The floor covering concentrates on the soft categories as carpets and rugs. Apart the market is filled with huge variety of fabric blended tiles which play a vital role in floor of today’s civil engineering. The wall coverings consist of fabric permanent and semi permanent walls, fabric wall papers and curtains, draperies and its accessories.

Consumer demand for affordable, easy to care floor covering led to the increase in the availability of polyester carpets, although this segment was dominated by wool, acrylic and polypropylene carpets. Non-woven wall to wall carpets are gaining popularity. Adequate strength, higher bulk, fastness, affordability, resilience and easy care make polyester carpet one of the best choices. Since wall to wall carpets serves as a good insulator as well as provides dust free environment, there is a great demand in the IT industry of India. The characteristics of floor coverings and their area of application are one mm thickness used in study centers and residential areas, 1.5 mm for departmental stores and computer rooms and 2 mm thickness used in electronics rooms and industrial areas. Large variety of designs like wood, mosaic, marble, ceramic, geometrical patterns are produced in vinyl flooring according to suit to various applications like offices, bank, airport and shopping complex. The floor covering are classified as PVC flooring & Printed PVC flooring, Non-woven carpets, Woolen carpets, Carpets / floor coverings of polypropylene and blends of polyester.

Wall covering are flooded with variety of fabricated tiles and fabric wall coverings. Apart from the conventional tiles which are featured with variety of designs, colors, the demand for special finishes like UV resistance, fire proof, high performance wall covering that are dramatic to light; environment safe with coatings which manage moisture around is increasing. Most of these coverings are made of high twist yarn with moderate weight. Curtains and draperies are available as woven, non woven and knitted fabrics. Usually they are made of cotton and polyester blends.

Their designs and colors vary to suit the place of usage.

1.4.6 Scaffolding nets

Scaffolding nets are lightweight fabric used to cover the building under construction which acts as a bi-fold barrier to improve safety. It also prevents the falling out of waste from building and hides out unsightly work areas. High density polyethylene, UV stabilized monofilament yarns are used for knit scaffolding nets. Scaffolding nets are available in wide range of shades and GSM. The rise in construction activity has increased more demand for the scaffolding nets.

1.5 CONCLUSION

Today more and more building for research centers, information technology and computer based jobs are shooting up which in turn has raised the need for buildtech. In this part of the module we have just touched upon the importance aspects of build tech but each section is growing daily. In India houses with rain water harvesting system and earthquake resistance have become mandatory. Similarly each country put forth various concept like recently Italy and China are looking forward to vertical forestry, where in each tall building of 20 to 100 floors are designed with space for growing trees. The tree growing areas are development with the concert structures well supported with jute blends and cotton polyester blends. In this manner build tech is growing daily and one has to wait to see more changes in textiles and textiles processes used in built tech.

2. MOBILE TEXTILES

   2.1 INTRODUCTION

Textiles have been a part of locomotives from days ago. They were used for protection and comfort during travel, like seats, clothing and parts of the vehicles like glass wipers which are used for the proper functioning of the vehicle. The application of technical textiles products in vehicles such as trucks, cars, aerospace, ships, buses and space crafts are categorized as mobile tech products. This sector is the largest sector of technical textiles that find single end use. The growth in automotive sector has created more demand for mobile tech products. Mobile textile products range from simple handle bar covers in bicycles to high tech seven layer space suits. Since more importance is given by the government for road safety measures there is an increase in the production of helmets, seatbelts and air bags.

2.2 OBJECTIVES

At the end of the session the learner will be able to

•   Know the various products and their end uses in mobile tech segment.
•    Understand the significance of mobile tech products in daily life.

2.3 DEFENITION

Ø  Any fiber, yarn, or fabric used for the manufacture of textiles used in vehicles as whole or as a compound to enable the functioning of the vehicle and comfort of the traveler is rightly called as mobile tech.

2.4 CLASSIFICATION OF MOBILTECH

The mobile tech products are generally classified into two classes such as visible components and concealed components. As the name indicates the visible components are components which are visually seen. It comprises of products such as carpets, headliners and seat upholstery. Concealed components are components which are usually a part of the vehicles components which help in the functioning of the vehicle. It include tier cords, composite reinforcements used for automotive bodies, military and civil aircraft bodies, wings components, liners, noise vibration and harness.

2.3 TYPES OF MOBILTEX PRODUCTS

2.3.1 Seat belt

The role of seat belts is to secure the travelers safely in the vehicle from harsh movements during accident or similar incidents to minimize the injuries. They are woven in a webbing pattern,  narrow in width from high tensile polyester or nylon filament yarns between 100 and 3000 denier. Smoothness in webbing is desired since it will directly influence withdrawal behavior and physical attributes. Load specification is one of the important criterions required for seat belts to be used in vehicles and the desired load bearing capacity is 1500 kilograms. The strict rules from Central Motor Vehicle Regulation (CMVR) and government have made the use of seat belts mandatory in vehicles. The vital features required for seat belts are resistance to abrasion, light and heat and easiness to fasten as well as to remove and good retraction behavior. The quantity of seat belt required per seat is about 2.5 to 3 meters. Seat belts are classified as Static belts and Emergency Locking Retractor belts (ELR).

2.3.2 Car upholstery: Seat Cover fabrics

The availability and requirement for luxuries, comfort as well as economical models of vehicles has increased the demand for seat covers of various ranges. Seat covers are generally woven in power looms using vinyl, velvet, cotton and leather. Cotton or synthetic yarns with a denier ranging 500 to 1330 are also used for the making of car seat covers. The characteristics required for seat covers are durability, wear resistance, flexibility, ultra-violet fade, water-proofing and stretch ability. Similar seat covers are used in other vehicles also.

2.3.3 Car Body Covers

The car body covers are made up from HDPE, PVC reinforced cotton, nylon or canvas. It is used to cover the car and protect it from sun, rain and dust. Its price ranges from Rs. 600 to 1100.

2.3.4 Automobile interior carpets

Automobiles, especially passenger carries like cabs, buses, airplanes are equipped with carpets in the cabin and parcel shelf. Non-woven textile materials of 500 GSM and 3mm thickness primarily made from polypropylene fibres are used as carpets. The carpets need to be of high durability, tensile strength, high abrasion resistance, low in-flammability and good compression recovery.

2.3.5 Headliners

Headliners are light weight non-woven composite materials consists of a face fabric with foam or non-woven backing of 185-220 GSM, used as roofing materials in automobiles. Most of the headliners consist of a tricot knit fabric so as to provide soft touch and even appearance. The fabric will be adhered by the means of melted polyurethane foam. Good aesthetics and suitable sound damping properties are the required characteristics for headliners. The raw materials used for making headliners are PSF, polyurethane or polypropylene core sprayed between two reinforcing layers. The main machinery for non-woven headliners manufacturing are needle looms.

2.3.6 Insulation Felts

Insulation Felts are also known as Noise, Vibration, and Harshness products (NVH). The chief application areas of insulation felts are for thermal insulation and audio in the automobiles such as bonnet liner, wheelhouse and outer floor under shield and outer dash. They are helpful in reducing the noise and protecting inside of the car. They are fabricated by needle punching, resin bonding and thermoplastic. The felts are soft and it can be used with or without harder backing.

2.3. 7 Sunvisors / Sunblinds

The sunvisors/ sunblinds are located in the interiors of four-wheelers just above the windshield and are used to block the sun light entering through windshield thus to reduce the hindrance created by sunlight to the driver and passenger. They are made up of are three parts as the blinds, the backbone made of polypropylene, the scrim made with coarse woven reinforcement fabric and upholstery fabricated with artificial leather. The fibres used for making the core of sun blinds are kenaf, polypropylene and polyethylene tetra fluoride or blend of these.

2.3.8 Airbags

Air bags are the inflatable protective equipment that reduces injuries in an accident or its impact in coordination with the seat belt. Lighter denier, silicone coated nylon 66 or polyamides 66 are used to make them. Almost, 1.8 square meter of fabric is required for making an airbag. The cost  of an air bag is about Rs. 5000 and if it is once inflated it need to be replaced with fresh one. In the recent times China has manufactured a set of air bags to suit two wheels also which the drivers has to wear like a helmet. It looks a bonnet. About 80% air bags are imports from Korea.

2.3.9 Helmets

Helmets are being used as protecting head gear for two wheelers. It consists of an inner layer made up of polypropylene or foam and an outer layer made out of glass, plastic and other synthetic fibres. Its primary function is to absorb the impact of a crash and to prevent the primary injury to the brain. The outer shell helps to prevent the puncturing of the skull from sharp objects on contact with road. The inner foam lining reduces the chance of primary brain injury. The two kinds of helmets available are Full face helmet and Open face helmet.

The important features of the helmets are protection of head, quick release of chin strap, clear vision and adequate ventilation. The outer shell of the helmet is made from Polypropylene or glass fibre, plastic, which is tough in nature. The inner surface of the shell is made by density padding to provide cushion effect to the wearer. In India, The Bureau of Indian Standards (BIS) has made quality control mandatory for all helmets. All helmets must have ISI mark – IS: 4151 to meet BIS standards.

2.3. 10 Tyre cord fabric

Tyre cord fabric is primarily used as reinforcements of bias tyres to offer strength to a vehicles tyre. Nylon 6 grey as well as dipped tyre cord fabrics having fatigue resistance, hot air shrinkage, high strength and elongation, ply twist, high adhesion characteristics and impact resistance are best suited for tyer cords.

2.3. 11 Technical Textiles in Aerospace

The aerospace textiles consists of two section as textiles used in airplanes and ones used in space ways. Due to hygiene and ease of use, disposable nonwoven fabrics are largely used in airlines industry. The most common textiles used in the air lines are

• Tea pot cover :100% Polypropylene Spun bonded 70 GSM, 16 cms by 14 cms
• Disposable Headrest cover: 100% Polypropylene Spun bonded 40-50 GSM for domestic flights and 60- 90 GSM for international flights Headphone bag (premier) :100% Polypropylene Spunbonded40 GSM, 22 cms by 24 cms

Apart from these visible components there is a huge list of other items which sever as part of the air craft also. They are all made up of light weight high twist, synthetic fabrics. These fabrics are enhanced with fire proof, stain resistance finishes. Some other common air lines textiles are aircraft webbings and aircraft upholstery. The major space textiles include the seven layer space suit and the compounds attached to the space ship which is specifically designed to with high performance fibers and given special finishes.

2.3.12 Technical Textiles in Railways

Railways have long list of textile materials used in enhancing the movement of the train and comfort of the passengers. This ranges from furnishing in air conditional compartments to textiles used in brake wires. Furnishings are modified as per the type of train and class of the compartment. The most prominent textiles in railways are seat covers. Railways seat cover fabric is made from single or multiples poly vinyl film layers with or without backing cloth and polyurethane foam.

2.3.13 Technical Textiles in Water ways

Water ways include small rafts to big ships and submarines. The textiles used in these vehicles are called as marine textiles. The most common textiles seen in water ways are sail cloth, tie up and anchor ropes, boat covers, life jackets, suits, nets, headliners, composites and decorative floorings and furnishings. Polypropylene, Polyester, viscose are the common used fibers. Apart glass, carbon are also used. Reinforced composite fabrics help in building the outer structure of the vehicles. The major properties of these textiles are corrosion resistance, low bearing weights, resistance to abrasion, flame, UV rays, fatigue and improved resistances to damping, microbial growth and salt water. Depending upon the product and their uses their properties vary.Weaving, kitting and non woven techniques are used for the making of the marine textile products.

2.3. CONCLUSION

With increase in roads and tourism there has been an increase in the number of vehicles and need to assure the comfort and safety of one’s journey. This has paved the foundation for growth in mobile textiles. Mobile or automotive textiles are one of the fast growing sectors which witnesses changes every second. In this part of the module we have seen a glance of the most commonly used mobile textiles.

Web links

• https://www.textilemedia.com/textile-reports/technical-textiles/transport-textiles/
• www.innovationintextiles.com/transport-aerospace/
• www.innovationintextiles.com/transport-aerospace/
• technotex.gov.in/buildtech.html
• www.technicaltextile.gov.in › Segments