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Wood viscose

5,857 bytes added, 10:50, 24 April 2015
== Potential impacts ==
===Cultivation===
Wood feedstock may be sourced from ancient and endangered forest.[2]
===Processing===
To transform hardwood-derived materials into silky fabric, the cellulose must be separated from other compounds found in trees. Sodium hydroxide (caustic soda) and sodium sulfide are commonly used to remove the lignin that binds the wood fibres together, and in some cases bleach is required to whiten the pulp. In a complex process the pulp is steeped in caustic soda to produce alkali cellulose, which is then aged or oxidized before reacting with carbon disulfide to create sodium cellulose xanthate. This xanthate is dissolved in caustic soda to form a syrup-like spinning solution or “viscose,” which can then be extruded through a spinneret to form viscose fibres.[3]
The viscose manufacturing process is chemically intensive and requires copious amounts of water. Wastewater effluents from processing must be properly treated to avoid contamination of surrounding water bodies. Air emissions caused by the viscose process include sulfur, nitrous oxides, carbon disulfide and hydrogen disulfide. Chronic exposure to carbon disulfide can cause damage to the nervous system in humans.[3]
===Dyeing===
The dyeing processes for viscose is a multi-step process that involves ample amounts of water at high temperatures (50°-95°C), salt, acetic acid and caustic soda. Mild peroxide bleach may also be necessary to remove residues of sulfur.
===Consumer care/washing===
Viscose is typically dry-clean only, due to delicacy of the fabric when wet. Some types of viscose can be machine or handwashed.Electricity and water use in the care of the garment can cause significant environmental impacts. Certain chemicals used in dry-cleaning and at-home products have been reported to have detrimental effects on humans and the environment, and contribute to ozone depletion and can pollute wastewater.
===End of use===
According to the Federal Trade Commission (FTC) in the United States, viscose products are non-biodegradable because they will not break down in the required time under customary disposal conditions.[7]Viscose is typically used in fast-fashion garments that are worn and quickly discarded. If these garments end up in landfill, they are likely to remain there for decades.
==Optimize sustainability benefits==
{| class="wikitable"|• Discourage suppliers from using old-! style="background-colorgrowth trees as feedstock for viscose fabrics, especially those harvested from the following endangered forest areas:#66cdaaCanadian boreal forest;width:300pxcoastal temperate Rainforests of the Pacific Northwest;color:#ffffff" | OPPORTUNITY! style="background-color:#66cdaaUS;width:300pxChile;color:#ffffff" | BENEFITS! style="background-color:#66cdaa;width:300pxTropical forests of Indonesia;color:#ffffff" | CONSIDERATIONSand the Amazon.[2]|-| '''Know • Encourage suppliers to use raw materials sourced from responsibly managed forests registered in the difference between natural bamboo linen fabric, Forest Stewardship Council (FSC) certification system and bamboo made /or sourced from a viscose process.''' || || Bamboo viscose is chemically processed Programme for the Endorsement of Forest Certification schemes (PEFC) and has greater pollution impacts to water and airForest Stewardship Council (FSC) certified forests.[2]|-| '''Promote the use of linen from bamboo ===Lenzing Viscose®===Lenzing Viscose® gives more attention to overall sustainability. The various chemical and waste productsthat result from the production process are recycled or sold.''' || Once Viscose from Lenzing is PEFC certified, which means that the fibre raw material is extracted sourced from responsibly managed forests.Lenzing Viscose® and Lenzing Modal® Austria are the stemonly man-made fibres which are carbon neutral.===Lyocell===New forms of viscose-type materials are emerging, processing bamboo and can be made through various types of processes, including lyocell. Lyocell material properties are similar to traditional viscose and fibre production is also similar to that of generic viscose in that hardwood material is dissolved through an intensive chemical process into yarn a pulp, which is then extruded to form fibres. However, for linen lyocell, the solvent used to transform the pulp into fibre is largely mechanicalamine oxide (NMMO=N-Methyl-Morpholine-N-Oxide), with minimal environmental impactwhich is considered non-toxic. || The lyocell fibre manufacturing process also operates as a closed loop system, in which 99% of the solvent is recovered,|filtered and reused. Any remaining emissions are broken down harmlessly in biological wastewater treatment plants.[9]===OEKO- TEX certified viscose=== [10]| '''Promote the use of ozone bleaching processes to strip out the natural beige colour of linen OEKO-TEX is an independent, third party certifier that offers two certifications for textiles: OEKO-TEX 100 (from flaxfor products). <br /><br and OEKO-TEX 1000 (for production sites/>Promote the particular aesthetic of ozone bleach effectsfactories).''' || Ozone can used be with OEKO-TEX 100 label aims to ensure that products pose no water at allrisk to health. || Ozone has limited availability, OEKO-TEX certified products do not contain allergenic dye-stuffs and is relatively expensive since it requires investment in ozone generating equipmentdye-stuffs that form carcinogenic aryl-amines. <br /><br />Ozone processes produce The certification process includes thorough testing for a different aesthetic than chlorine derivative or permanganate bleachinglong list of chemicals. Specifically banned are: AZO dyes, carcinogenic and allergy-inducing dyes, pesticides, chlorinated phenols, extractable heavy metals, emissions of volatile components, and more.|}
==Availability==
There are a few suppliers in China that are currently offering viscose from PEFC and FSC certified forests. Expressing interest in PEFC and FSC certification can influence the supplier’s raw material sourcing strategy and lead to greater availability of responsibly sourced feedstock for viscose fabric.OEKO-TEK® Standard 100 certified viscose is available. Manufacturers can be found at: www.oeko-tex.com==Application==Viscose and lyocell can be used in a variety of textile woven and knitted applications. Depending on the weight and construction of the cloth, these fabrics may be suitable for shirts, skirts, dresses, evening gowns, home furnishings and bedding.
==Marketing opportunities==
'''lyocell process''' If processed with a lyocell process.<br/>
'''PEFC-certified''' Must be verified, and can be claimed on POS items at retail.<br/>
'''FSC-certified''' Must be verified, and can be claimed on POS items at retail.<br/>
'''Lenzing Viscose®''' If verified and used.<br/>
'''OEKO-TEK® Standard 100 certified''' If verified and used.<br/>
==Innovation opportunities==
1. Shift to existing environmentally beneficial fabrics when possible. These fabrics include fabric derived from organic cotton, recycled fabrics, hemp, flax, and dissolving pulp from bamboo and eucalyptus plantations that are PEFC or FSC-certified.<br/><br/>2. Use wood pulp from PEFC and FSC-certified plantations, and produce the fabric with lyocell process. Communicate the difference between the viscose and lyocell processes to consumers on your website and hangtags.<br/><br/>3. Encouraging handwashing on the hangtag and labeling/POS would influence the consumer to take an active role in reducing environmental impacts of viscose at the consumer washing stage.
==Sources==
1. https://www.swicofil.com/products/200viscose.html2. https://www.canopy.org/index.php3. oecotextiles.wordpress.com/2009/08/19/348/4. https://www.eksoy.com/PDF/VISCOSE%20AND%20BAMBOO.pdf5. textilefashionstudy.com/process-flow-chart-of-viscose-fabric-dyeing/6. textilelearner.blogspot.com/2012/09/100-viscose-fabric-dyeing-method-dyeing.html7. ftc.gov/opa/2009/08/bamboo.shtm8. lenzinginnovation.lenzing.com/fileadmin/template/pdf/Texworld_USA_2012/16_01_2012_2_PM_Lenzing_Edelweiss.pdf9. https://www.lenzing.com/sites/botanicprinciples/website/index.htm10. https://www.OEKO-TEK.com/media/downloads/Factsheet_OETS_100_EN.pdf
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