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GE: Ecomagination Challenge: Ideas

2010-09-20T12:37:00.000-07:00

GE is coming up with an eco-imagination challenge for the following three categories

Create - Renewable Energy
Connect - Grid Efficiency
Use - EcoHomes/EcoBuildings

Anybody can share their ideas in the above threee challenges and the winner will get awarded with 200 million US dollars. Textile is competing in all fields and it has promising future in making the earth greener. Post your textile ideas that can save planet and get rewarded. Click the below link to learn more and post your ideas. Good luck!

GE: Ecomagination Challenge: Ideas

Textiles as UV Protection

2010-09-19T18:30:00.000-07:00

With the depletion of ozone layer, more and more people are realizing the health threat posed by the sun. Textiles can provide protection from ultraviolet rays to a greater or lesser extent, depending on the type and construction of the fabric. When UV rays impinge on a textile material, the radiation can be completely reflected, dispersed or absorbed.

Selection of textile fiber is significant in providing the protection. The protection factor of greige cotton is considerably higher than bleached cotton, because the natural pigments, pectins and waxes provide UV absorption. Polyamide fibers are quite permeable to UV rays, whereas polyester fibers posses strong absorption. Artificial fibers can be produced with good protection against sun rays by simply adding titanium dioxide, which in integrated in polyester and poly-acrylic fibers. Titanium dioxide provides excellent UV protection and also provides some cooling effect. The protection can be further enhanced by using cationic dyes.

Fabric construction also plays an important role in engineering textile products for UV absorption. Higher density of fabric, reduces the UV penetration. So by carefully selecting the cover factor of the fabric, the protection can be provided. Similarly high lustrous fibers reflects most of the rays back to atmosphere.

There are special coating available to absorb the rays. They are titanium dioxide, zinc oxide, aluminum silicate, benzo-triazole, hydrobenzophenone, phenyltriazine, etc. The textile material can be coated with the above mentioned to provide additional protection. Also by selecting the depth of color, the textile material can be provided with additional protection.
To brief, the UV protection of a textile material is influenced by the following factor;

Fiber type
Yarn construction
Fabric construction
Fabric color
Fabric finish
Fabric surface characteristics like luster

Gas-Solid Filtration

2010-09-12T19:41:00.000-07:00

Textile medium has been used as an aid for filtration since old ages. Early humans used woven sacks made of cotton or wool for filtration. During the industrial revolution, reverse air cleaning with cotton or woolen bags were popular. With the introduction of man-made fibers, fabric filtration seen a huge success in the industrial which widened its applications [high temperature filtration, micro dust collection, etc]. Its literally used in almost all types of industries to collected dust from the gas.

Their are four types of Gas-solid filtration systems currently available for the industries. They are textile filtration systems, electrostatic precipitator, centrifugal filtration system and wet filtration system. Among these, textile and electrostatic precipitator systems are used much. Textile filtration systems are preferred much because of its high filtration efficiency and can be engineered to suit the industry.

Textile filtration for gas-solid can be broadly divided into the following;

Membrane filtration
Fiber filtration
Fabric filtration

Membrane filtration can achieve high filtration efficiency but only can be used for small scale like laboratory. Fiber filtration uses a layer of loose fibers to collect the dust and it cannot not be reused again. Advantages like high cleaning efficiency, renewable and wide scope of application made the fabric as an effective choice for filtration. Cleaning process of the fabric filters are little different from other methods of filtration. This is the only filtration method where the accumulated dust itself plays an important role in the cleaning efficiency of the fabric filtration because these dust will act like a filter medium.

Fabric filters also can be easily engineered to suit the different types of industries. By simply changing the cover factor of the fabrics we can achieve the necessary cleaning efficiency. Also by selecting suitable fibers we can cover wide scope of application; for example: Nomex or glass fiber fabric for high temperature filtration, Felts for collecting small particles, PP fabric filters for chemical industries etc..

Supercritical Dyeing

2010-09-06T15:36:00.000-07:00

Who said water is the only medium that is used to carry dyes into the fibers. Dyecoo textile systems is introducing another medium that can be used as a dyeing medium and that medium is none other than Carbon dioxide; the gas that is responsible for the global temperature rise.

If we use water as a medium, we need additional water treatment process to collect unabsorbed dyes and prevent pollution. The pollution control regulations make the water treatment process necessary for the dyeing plant before it is released into the environment. This process obviously increased the cost of dyeing of the textile material. We are living in the world of scarcity and this applies to water also. Water is precious and we cannot afford to waste it.

This is how the process works: Carbon dioxide is heated to around 120⁰C or 250⁰ F in a high-pressure chamber at 250 bar. Under these conditions, the carbon dioxide will be converted to supercritical state; a state at which the gas converts to expanded liquid that allows the dissolution of dye compounds. Under these conditions, the textile fiber (eg: PET/cotton) expands and allows the medium to go through its pores. The medium leaves the pores of the fiber leaving the dye compounds in the pores. After that the medium is recycled and used again. This process completely eliminates the use of water and it is environmentally safe and effective.

If the industry starts using this medium for dyeing purpose, may be we can remove some of the global warming ingredient from the atmosphere and also we can save some of our precious water. This makes the industry looks cool and makes the environment feels cool :-). For more details about the process please refer to the company’s website [Dyecoo textile systems].

Trabecular Metal Implants

2010-08-31T06:55:00.000-07:00

Trabecular Metal is a bio-material composed of tantalum(Ta) on a graphic scaffold. Tantalum is one of the most bio compatible material known to man. This bio-material is developed and patented by Implex Corporation which is now taken over by Zimmer. Inc.[ZMH].Cellular structure of Trabecular metal resembles very close to Trabecular bone, a type of bone found in the joints, that is why this material got its name as "Trabecular".

Understanding the behavior of material is very important in developing and engineering its products. Trabecular materials are physically and mechanically more similar to human bones than any other bio implants. These implants has more porosity and flexibility that allows the infiltration of bone growth into its pores. Because of it, the bond between Trabecular metal implant and bone is as good as the bond between human bone and ligaments. More over the elastic modulus of this implant is lower (around 3 Gpa) than most metal implants (Titanium alloy - around 110 Gpa, Carbon fiber - 18) that provides physiological load transfer to bones. The company claims, Trabecular implants have the following advantages over other counterparts;

High strength to weight ratio.
High porosity ( more than 70% of material).
Low coefficient of friction.
Low antigenicity which provides less immune resistance.
Low elastic modulus.
Physical and mechanical properties similar to bone.
Provides stronger bond between bone and implant.

Due to its advantages over other bio implants, Trabecular metal implants are most preferred as far as bone implants are concerned. Research of the material is still going on with University of Notre Dame, Zimmer. Inc., and Implex Corp. For more information, please refer to their sites.

Four Point System

2010-08-27T09:25:00.000-07:00

Quality control department is responsible for producing a good quality product. How do they achieve it?..

Quality assurance or quality control department will perform the necessary inspection of the fabric to make sure it is matching the specification and they also make sure it is defect free [slubs, hole, missing yarn, conspicuous yarn variation,end out, soiled yarn, wrong yarn, dye spot, color shade/smudge, needle line, etc.]. They perform frequent random inspection of the fabric to determine the efficiency of the department which helps to identify and correct the problem. This reduces the waste produced in the department and also helps to produce a good quality product.

Manufacturer should certify their product as per the specification provided by the customer. Manufacturer and customer should mutually agree to that grading system to prevent confusion or conflict. It helps to prevent return of the goods due to disagreement in terms of number of defects and its particulars (length, width, front/back...). So a

standard grading system is used to identify the defect and grade it. A grading system has been developed by American Society for Quality Control (ASQC) and is called Four point grading system.

Four point system is a fabric grading system developed to assign points to the defects based on its size and type. In this grading system, points will be assigned to the fabric based on number of defects and its lengths. The details of grading as follows;

Size of defect Number of penalty points

3" or less 1

Over 3" to 6" 2

Over 6" to 9" 3

Over 9" 4

Fabric will be graded and points will be assigned as per the above guidelines. Then the fabric will be classified as first class or second class fabric using the below guidelines.

Penalty points per 100 sq/yd

50" or less in width More than 50" in width Class

Less than 41 points Less than 45 points First

More than 40 points More than 44 points Second

General guidelines:

Fabric should not have more than 1" bow or 0.5" bias for 60" width and this tolerance shall not exceed 2% bow and 2.5% bias on other widths.
No yard shall be assigned more than 4 points.
Defect should be counted only on face side.

For more information regarding the grading system, please refer to ASTM D5430.

Nano Fibers: An example of complex engineering

2010-08-25T12:27:00.000-07:00

I was reading about the conference that is about to happen in Raleigh, NC from Aug 30 to Sep 1, 2010. This conference is named as " Nano Fibers for the Third Millennium" and is organized by Elamrco Inc and NCSU. Elmarco Inc is a manufacurer of customized industrial solutions for the semi conductor industry. The company in combiation with Technical University of Liberec (TUL) introduced the first prototype of NanoSpider TM to manufacture organic or inorganic nano fibers. During the conference, oral presentations and poster presentations related to nano fibers will be conducted.

NanoSpider TM technology is a patented technology and is an electro spinning method of producing nano fibers. As you know, nano fibers are highy engineered fiber with diameter 200 times lesser than human hair. Some advantages of fabric made of nano fibers includes the following

Low density
Greater surface area
Less pore size
High porosity
Good breathability

With NanoSpider TM technology, it is possible to manufacture ceramic nano fibers. One such example is titanium dioxide fiber which is used in the semi conductor industry especially in the photo-voltaic technology, it is used as catalitic active material to absorb combustion gases (carbon dioxide, carbon monoxide, nitrogen dioxide, etc..), it is used as photocatalysis for cleaning industry and also used in cosmetic industry to absorb UV rays.

Published by Textile Vault.

Cotton Fiber Properties

2010-08-24T10:31:00.000-07:00

Who doesn't like to wear cotton?. It is true that the invention of manmade fibers made the cotton industry suffer a little, but it is back in the lead again. People are trying to go green and its comfirtability cannot be compromised with atrificial fibers. Cotton is a natural fiber and its tradition go back to centuries. Application of cotton fibers/fabrics are many and it is determined by the properties of the fibers.

Cotton plant belong to the family "Malvaceae" [Genus - Gossypium] and it can grow up to 9ft high. The seeds are contained in the boll and is surrounded by fibers. These fibers are graded based on their length, uniformity, strength, maturuty, color and foreign matters. Properties of cotton fibers are as follow;

Staple Length : 1/8 - 2.5 inch
Dry Tenacity : 3.00 - 4.90 grams/denier
Wet Tenacity : 3.30 - 6.70 grams/denier
Density : 1.54 grams/cc
Breaking Elongation : 3 - 9.5%
Moisture Regain : 7%
Average Toughness : 0.16 gf.cm/den.cm
Elastic Recovery : 74% after 2% elongation
Identification :

Fiber leaves fine gray ash and no bead after agnition. Burns/smells like paper with amber or yellow flame.
Single elongated cell with apperance as flat and spirally twisted ribbon like form with convolutions. But mercerized cotton does not show the natural twist.
Dissolves in 80% cold sulfuric acid.
Cotton feels cool to touch.

Heat: Decompose @ 550 F, Safe ironing @ 425 F
Acids: Disintegrated with cold concentrated acids of hot dilute weak acids.
Can be blended with almost all fibers.

Welcome to Textile Vault

2010-08-19T18:35:00.000-07:00

Welcome all! This blog is created to share the knowledge of textiles. I will be posting my personal experiences and my knowledge of textile to you. Thank you for visiting.

TEXTILE IS POWERFUL. Their is no limit for its usage and can be engineered to suit the performance or needs. Textile helps to make our life colorful, helps to stand among others, help to create attention, helps to satisfy our necessities, helps to make things lighter, stronger & durable, and finally helps to keep our earth clean. Wondering how? Read the blog to get all informations.

Thanks,
Textile Vault Team