Changes

==Vacuum suction==

Another technique that has been tested is ''vacuum suction''. The excess liquid is sucked through a column from the fabric after dipping. Uneven woven edges can cause problems and with the edge not properly sealed the vacuum varied and dewatering was uneven. Increasing in usage of the technique has been substantial since the problems with edge seal has been solved by using a flexible tube. The equipment works best on normal fabrics that are not too sparse and that can improve dewatering significantly.

* '''At pre-treatments''': The equipment delivers an effective output of the various washing and rinsing liquids including an efficient dewatering.

In order to produce fabrics with various protection functions they can be based either on a fiber material that haves particular characteristics already during manufacture or it can subsequently provide the material properties through preparation. The latter method is most common.

A fabric can be made water and oil repellent by a polymer coat put on the fabric. This makes the fabric completely sealed which can cause comfort problems since the body's evaporation and perspiration cannot be vented. The fibrous material can also be made water and oil repellent by the fiber surfaces that have low surface energy that is not wetted by water or oil. Since ancient times, there have been treatments with waxes, metal soaps and paraffin. These treatments will repel water, but they have not been able to resist oils. Silicone can provide water repellency and in some cases oil repellency. The treatments with waxes, paraffin, metal soaps and silicones had limited wash-resistant functions. Fluorocarbons are becoming increasingly common in use to provide water, oil and stain repellency, fluorocarbons have good wash fastness if you follow the special washing instructions.

DWR (durable water repellent) is a coating added to fabrics at the factory. Durable water repellents (DWRs) are applied to garments and products to allow for breathability and water repellency. Common factory-applied treatments are fluorochemicals. Certain DWRs are known to have persistent, bioaccumulative and toxicological effects on the environment. The durable water repellent coatings used in the fashion and textile industry are currently not bio-based or biodegradable. Water repellent coatings also inhibit recyclability.

• Work with manufacturers to create bio-based or biodegradable water repellent finishes.<br/>

• Investigate durable water repellents from alternative, renewable non-toxic resources, such as castor oil.

• Investigate short chain fluorocarbons that do not degrade into PFOA.<br/>

• Investigate stain resistant finishes that do not involve the use of PFOA, such as finishes from DuPont.<br/>

Synthetic and blended fabrics are antistatic treated to reduce the problem of static charge in the manufacturing and use. Usually added substances are quaternary ammonium or acid amides and ethoxylates which increase the conductivity of the fiber surfaces. The treatment is done either by its own final impregnation or in addition to the normal end of the treatment. Wash resistance of antistatic treated products varies.

Need for mold protection is greatest on natural fibers since they are easier to be attacked by mildew and rot than synthetic fibers. It is not allowed to perform mold protection on textile products in Sweden. Even though, goods with this type of impregnation still reaches the country through imports.

Of the chemicals used in flame retardant treatment there has recently been paid special attention to brominated biphenyls and biphenyl. It is found that they accumulate in aquatic organisms. These [[flame retardants]] have been removed in manufacturing in Sweden. Although the brominated compound hexabromcyclododekan (HBCD) have been shown to be stored in the environment. It has been found in fish from Viskan (river in southwest Sweden) (study by the Environmental Protection Agency 1995/96). For this reason the Swedish textile industry sharply reduced emissions of this substance. Conclusions indicate that the substance can be classed as [[bio accumulative]] and very [[toxic]] to aquatic organisms. Also the use of other [[halogenated flame retardants]] have been severely restricted and the same applies to retardant fibers. These are produced by copolymerization between vinyl chloride (mod acrylic). Chlorinated paraffin are toxic to aquatic organisms and bio accumulating. Chlorinated paraffin with a high degree of chlorination is also persistent, i.e. Non-degradable. Antimony compounds are hazardous and can be contaminated with lead and arsenic. Phosphates (Propane and Pyrovatex) are not toxic but are persistent and can be potentially [[bio accumulative]]. In addition, they can cause malfunctions if they are placed in water-cleaning and treatment plants. [[Melamine]], used in conjunction with the phosphates to achieve wash-resistant flame retardants, has low acute toxicity to aquatic organisms and low biodegradability.

Another important issue is the appearance of purity - especially on white fabrics where every little smudge is visible and remaining traces of dirt are visible even after washing. To make the fabric resistant to dirt, the same type of treatment is used as for water and oil-repellent treatment. These treatments means that dirt often get stuck in the form of aqueous or oily film on the fibers and cannot wet the fibers so it will instead “purl off”. This is where the expression stain repellent has its origin. There are also treatments that will facilitate the cleaning of laundry. This makes the fiber materials more easily can release dirt. Treatment is done with substances that make the fiber surfaces hydrophilic and easier to wet (soil loosening). Examples of such substances are carboxymethylcellulose (CMC), polyacrylic acid or ethoxylates.

For wrinkle and dimensional stability treatments todays mostly used ones are cyclic urea without or with formaldehyde. Recently, the content of free formaldehyde is reduced by the health and allergy reasons. There is ideas of formaldehyde-free and formaldehyde poor substances. Although melamine formaldehyde compounds are used for these treatments (see Environmental facts protection treatments). The urea’s and melamine’s acute toxicity to aquatic organisms are strongly dependent on the amount of free formaldehyde and glyoxal (cyclic urea). Both aldehydes are readily biodegradable. No information was found regarding the degradability of partially reacted urea and melamine. In the case when softener is used it is often the same, describing the anti-static agent under the heading Environmental Facts - protective treatment agent ,page 46. For soil-repellent treatment agent refers to substances for water and oil repellency, since they are similar. Regarding soil release treatments they are essentially hydrophilic and readily soluble in water. Polyacrylic acid with a low degree of polymerization is easily degradable in aquatic environments, while CMC and ethoxylates are said to be more persistent. Allergic rash of textiles due to formaldehyde was for about 25 years ago are quite common but are now very uncommon.

==Sources==

[[Textile Environmental Handbook]]