history of printing

History of printing Technologies Woodblock printing 200 AD Movable type 1040 Intaglio 1430s Printing press 1439 Lithography 1796 Offset press by 1800s Chromolithography 1837 Rotary press 1843 Flexography 1890s Screen-printing 1907 Dye-sublimation 1957 Photocopier 1960s Pad printing 1960s Laser printer 1969 Dot matrix printer 1970 Thermal printer Inkjet printer 1976 Digital press 1993 3D printing

pollution prevention in textile dyeing n printing

Pollution Prevention Through Automation in Textile Dyeing and Printing Textile wet processing (i.e. preparation, dyeing, printing and chemical finishing) has always been considered one of the worst industrial sectors in terms of water consumption and pollution. In treating 1 ton of cotton fabric the composite waste stream may have 200-600 p.p.m. BOD, 1.000 to 1.600 p.p.m. of total solids and 30 to 50 p.p.m. of suspended solids contained in a volume of 50 to 160 m3. For wool the effluent load is even higher, for 1 ton of scoured wool the composite waste stream would have 430 to 1.200 p.p.m. BOD and around 6.500 p.p.m. total solids contained in a volume of 100 to 230 m3. Many textile companies invest - or plan to invest - heavily in effluent treatment, in many cases not knowing that the pollution load may be reduced by 30-50% by applying techniques of pollution prevention, such as: reduction of wastewater volume by good housekeeping, counterflow processing, reuse of process water, automation of the machinery reduction of the amount of dyes and chemicals used by good housekeeping process optimization recovery and reuse of process chemicals, automation of the machinery computerized recipe optimization When we speak about automation in textile dyeing and printing, we mean one or more (or all) of the following steps: Programmable process control (by microprocessors) of the machinery; dissolving and dispensing of the dyes, pigments and chemicals in a central colour kitchen; computer-controlled weighing of solid material with automatic stock control and the printing of recipe and process cards; colour measurement, computerized colour matching; central computer (network), computerized management system Which of the above, and in what order, should be implemented depends a great deal on what is the purpose of automation. In order to improve the quality a) and c) are the most important, to save man-power a) and b) would be recommended, while for cost reduction d) is far the most efficient. If our aim is better service to our customers: right-first-time production, quick response to the client's request and just-on-time delivery, we have to implement full automation from a) to e). When our goal is pollution prevention, every automation step helps, but the first four of the list above would bring the most immediate results. Programmable process control (by microprocessors) of the machinery Full control of the processes results in 10-30% saving in water and energy usage as well as 5-15% saving in dyes and chemicals (in addition to significant saving in labour, and improvement in quality). Dissolving and dispensing of the dyes, pigments and chemicals in a central colour kitchen. 5-10% savings in dyes, pigments and chemicals (in addition to significant saving in labour, and improvement in quality). Computer-controlled weighing of solid material with automatic stock control and the printing of recipe and process cards. 10-15% savings in dyes, pigments and chemicals (in addition to significant improvement in quality). Colour measurement, computerized colour matching Up to 30-40% savings in dyes and pigments (in addition to significant improvement in quality). Needless to say, all the dyestuffs, pigments and chemical products "saved" by any of the above mentioned methods are also saved from the effluent. The greatest attraction of pollution prevention through automation is the simultaneous result of significant cost savings both in the production and in the effluent treatment. The costs of automation are relatively low, typical Return of Investment figures are in the range of 3 months to 1 year, not calculating the quality and reliability improvements, and neither the savings achieved in investing in and running a smaller effluent treatment plant.

Different types of Fabrics

Different types of Fabrics made out of different fibres

Pure Linen fabric





Pure Cotton fabric

Pure Polyester fabric

Pure cotton Fabric

Pur Silk fabric

speciality polyester fibre

SPECIALITY FIBRES IN POLYESTER:
HIGH/LOW SHRINK FIBRES: The high shrink fibre shrinks upto 50% at 100 degree C while that of low shrinkage is 1%. The high shrink fibre enable fabrics with high density to be produced and is particularly used in artificaial leather and high density felt. Low shrinkage fibre is recommended for air filters used in hot air, furniture, shoes etc.
MICRO DENIER: Available in 0.5/0.7/0.8 deniers in cutlengths 32/38 mm. Ideal for high class shirts, suitings, ladies dress material because of its exceptional soft feel. It is also available in siliconised finish for pillows. To get the best results, it is suggested that the blend be polyester rich and the reed/pick of the fabric be heavy.
FLAME RETARDANT: Has to be used by law in furnishings / curtains, etc where a large number of people gather - like in cinema theatres, buses, cars etc in Europe and USA. It is recommended for curtains, seat covers, car mats, automotive interior, aircraft interiors etc.
CATIONIC DYEABLE: Gives very brilliant shades with acid colours in dyeing / printing. Ideal for ladies wear
EASY DYEABLE: Can be dyed with disperse Dyes @98 degrees C without the need for HTHP equipment. Ideal for village handicrafts etc.
LOW PILL: In 2 and 3 deniers, for suiting end use and knitwear fibre with low tenacity of 3 to 3.5 gm/denier, so that pills which forms during use fall away easily.
ANTIBACTERIAL:It is antibacterial throughout the wear life of the garment inspite repeated washing. Suggested uses are underwears, socks, sports, blankets and air conditioning filters
SUPER HIGH TENACITY: It is above 7 g/denier and it is mainly used for sewing threads. Low dry heat shrinkage is also recommended for this purpose. Standard denier recommended is 1.2 and today 0.8 is also available.
MODIFIED CROSS SECTION: In this there are TRILOBAL, TRIANGULAR, FLAT, DOG BONE and HOLLOW FIBRES with single and multiple hollows. Trilobal fibre gives good feel. Triangular fibre gives excellent lustre. Flat and dog bone fibres are recommended for furnishings, while hollow fibres are used as filling fibres in pillows, quilts, beddings and padding. For pillows silicoised fibres is required. Some fibre producers offer hollow fibre with built in perfumes.
CONDUCTING FIBRE: This fibre has fine powder of stainless steel in it to make fibre conductive. Recommended as carpets for computer rooms.
LOW MELT FIBRE: It is a bi-component fibre with a modified polyester on the surface which softens at low temperature like 110 degree C while the core is standard polyester polymer. This fibre is used for binding non woven webs.

textile dyeing

Textile dyeing is concerned with organic (that is, carbon-based) compounds that can be dissolved in appropriate solvents, usually water. The dyes in solution are absorbed on the surface of the textile fibre then pass into the interior of the material by a process called diffusion.

The process of transferring the dye from solution to the fibre is called exhaustion, with 100% exhaustion meaning that there is no dye left in the dyebath solution. An important property of a dyeing is its levelness, in other words when the same depth of colour can be seen all over the material.

Another factor is good penetration, when the dye has penetrated deeply into the structure of the fibre, colouring it from the outer surface of the fibre to its interior.

Dye molecules are attracted by physical forces at the molecular level to the textile. The amount of this attraction is known as 'substantivity': the higher the substantivity the greater the attraction of the dye for the fibre.

Think of all the garments you own and imagine the things that they have to go through before you buy them and during use. Their colour has to resist fading when they are used or left out in sunlight. They have to be suitable for repeated washing without the colour running. But there are other factors as well.For example, the colour in your swimwear must also be fast to sea water and the chlorinated water used in the swimming pool. The blouse and shirt you wear next to your skin should not discolour because of the effects of perspiration (which can be either acid or alkali).

These are the sort of issues that dye manufacturers need to consider before launching dyes onto the market.Because of the wide range of end uses of coloured textiles, many tests have been developed to assess fastness. Testing involves comparing a dyed sample that has been exposed to an agency, for example to light or to washing, with an original, to assess accurately any change in shade or change in depth of colour. Up to a certain level, changes are considered by industry to be acceptable, depending on the end use of the dyed material. If these levels are exceeded the product fails the test.In washing fastness a sample is tested with so-called adjacent fabrics to assess the extent of staining of a piece of white fabric, similar to what happens when coloured garments are washed together with whites in a washing machine.

future textiles

THE AREAS OF FUTURE TEXTILES Though they are not always visible and may not make-up 100% of a product, here are some real life examples from within the main areas of the technical textiles sector: Medi-Tech (Medical Textiles) – allergy-free bedding and a woven fabric containing silver technology that can kill the MRSA bug are now available Build-Tech (Construction Textiles) – textile applications used within the construction industry including scaffold nets and roofing felts Cloth-Tech (Clothing Textiles) – an example is performance materials such as GORE-TEX which is waterproof, windproof and highly breathable Auto-Tech (Automotive Textiles) – did you know that the internal structure of a tyre is made-up from textile fibres including cotton, nylon and polyester? Aero-Tech (Aerospace Textiles) – woven fabric structures form part of composite materials used in the manufacture of aircrafts wings, as well as the main body of an aircraft Def-Tech (Defence Textiles) - found in the uniforms of the armed forces and emergency services, fibres can be flame-retardant and heat-resistant Agro-Tech (Agricultural textiles) – used in agriculture, horticulture, forestry and landscaping e.g. nets for protecting crops from weather and insect damage

FUTURE TEXTILES

THE AREAS OF FUTURE TEXTILES Though they are not always visible and may not make-up 100% of a product, here are some real life examples from within the main areas of the technical textiles sector: Medi-Tech (Medical Textiles) – allergy-free bedding and a woven fabric containing silver technology that can kill the MRSA bug are now available Build-Tech (Construction Textiles) – textile applications used within the construction industry including scaffold nets and roofing felts Cloth-Tech (Clothing Textiles) – an example is performance materials such as GORE-TEX which is waterproof, windproof and highly breathable Auto-Tech (Automotive Textiles) – did you know that the internal structure of a tyre is made-up from textile fibres including cotton, nylon and polyester? Aero-Tech (Aerospace Textiles) – woven fabric structures form part of composite materials used in the manufacture of aircrafts wings, as well as the main body of an aircraft Def-Tech (Defence Textiles) found in the uniforms of the armed forces and emergency services, fibres can be flame-retardant and heat-resistant Agro-Tech (Agricultural textiles) – used in agriculture, horticulture, forestry and landscaping e.g. nets for protecting crops from weather and insect damage Skillfast-UK. Part of the Skills for Business network of 25 employer-led Sector Skills Councils.

Fabric selection

Fabric Guide Cashmere: Gets its name from the Kashmir goat of India. Cashmere is a super soft luxury fabric, although is often mixed with wools or synthetics to keep costs down (this is how you can get cashmere in Target these days, for example). Advantages: Soft, luxurious look and feel, has a little bit of stretch, adapts to the temperature (keeps you warm in winter but cool in spring). Disadvantages: Many great cashmere lines (TSE, Lucien Pellat Finet, etc) do not make plus size cashmere items. Those that do often offer unstructured pieces, as opposed to ones that are body hugging. Also, cashmere is fragile, prone to snags, moth holes and pilling. Cotton: Natural fiber used in the majority of casual clothing on the market including many panties, t-shirts and workout gear. Advantages: Soft, easy fit, affordable, can be machine washed. Disadvantages: Often does not age well, color made fade after repeated washings. Linen: Natural fabric that comes from the flax plant. Linen is similar to cotton but stronger, and without any stretch. Advantages: Comfortable; breathes well. Disadvantages: Wrinkles easy; does not conform to the curves of the body, not dressy. Lycra/spandex: A strong, elastic, man-made fabric that is frequently blended with other fabrics to make them stretchier. Most bathing suits, sports bras, leggings and very clinging clothing items have a percentage of lycra in them. Advantages: When used as a small percentage of a fabric, lycra can add a little stretch without being too tight. Disadvantages: The greater the percentage of lycra or spandex in the garment, the tighter it will fit, clinging to areas you might not want to showcase. Sometimes it also doesn't breathe very well. Rayon: A man made fiber that is often used as an alternative to silk. Rayon is commonly found in dress and jacket linings, although it is also frequently used in less expensive evening wear. Advantages:Feels good to the touch, can sometimes give a look of quality at a reduced price. Disadvantages: Can sometimes look cheap, shiny rayon can become dull over time. Satin: A weave made from silk or man-made fibers like polyester, this thick fabric is most often utilized for evening and bridal wear. Advantages: Satin can be a fairly flattering fabric, and even polyester satins can look expensive. Look for satins that are lined, they skim the body a little better. Disadvantages: Can wrinkle or crease from sitting, can show sweat stains if it's a light color, usually doesn't have stretch to it unless it is cut on the bias. Silk: Comes from caterpillar cocoons. This is a luxury fabric with a shine to it. Silk is most often seen in evening wear, scarves, camisoles, and lingerie. Advantages: Silk looks and feels expensive and elegant. Disadvantages: Silk will lay against your body in a way that shows every lump and bump. Velvet: A tightly woven fabric with a thick pile to it, velvet can come in a variety of thicknesses and types. Velvet is most often seen in tops, tunics and evening wear. Advantages: Feels good to the touch, if it is cut on the bias or has stretch it will lay nicely on the body. Disadvantages: Some velvets can look cheap, can be hard to launder, depending on the style it can look very outdated. Wool: A fiber made from goats, sheep or other wooly animals. Wool is a warm fabric most often used for outerwear, sweaters, or winter pants. Advantages: Keeps you really warm. Disadvantages: Depending on the type, it can be really itchy, and can smell funny if it gets wet.

Hygiene Textiles - Antimicrobial Polyester

1) – Introduction.
Since the last part of the century an increasing improvement in
qualitative standards of human lifestyles has brought to a greater sense
of comfort, and cleanliness. People are more and more looking for fresh
public living surroundings and a higher level of hygiene in home areas.
A wide class of micro-organisms coexists in a natural equilibrium with
human body and living environments, but a rapid and uncontrolled
multiplication of even non pathogenic microbes can seriously
compromise the hygienic and healthy personal standards. Because of
their capillary spread in the human living spaces, the textiles have been
involved in this research of a growing quality of hygienic living
conditions.
Actually, several combinations of temperature, humidity and other
climate factors added to the presence of dust, soil and fat-stains on the
textile surfaces can transform the textiles themselves in an optimal
enrichment culture for a rapid multiplication of micro-organisms. In
such a case two contemporary effects occur: the first is an uncontrolled
proliferation from textile surfaces into the surrounding environment
with a consequent increase of bio-burden level and potential health risks
or, at least, of discomfort for the unpleasant odours produced by high
concentrations of micro-organisms; the second one is the onset of
degradation phenomena as colouring and discoloration of the textile
2
fibres. Many efforts have been performed by textile industry with the
aim to score two goals: the protection of the living environments and of
the textile fibres from an uncontrolled proliferation of microorganisms
like bacteria.
2) – Micro-organisms action on textile surfaces.
In the broad spectrum of existing bacteria there are pathogenic and
non-pathogenic organisms. Both of them can multiply abnormally on
the textile surfaces with an accumulation that compromises the hygienic
cleanliness.
Tab.1 shows some examples of pathogenic and non pathogenic microorganism.
Tab. 1
MICRO
ORGANISM
PATHOGENICIT
Y
EFFECTS
Bacillus subtilis Generally non
pathogenic
Food spoiling
occasionally conjunctivitis
Escherichia coli Low pathogenic Food spoiling
occasionally urinary bladder
infection
Klebsiella
pnuemoniae
Pathogenic Pneumonia,
urinary bladder infection
Pseudomonas
aeuroginosa
Pathogenic Multi-infections
Proteus vulgaris Low pathogenic Infiammations
Staphylococcus
epidermidis
Low pathogenic Surgical wound infections
Staphylococcus
aureus
Pathogenic Toxic shock, purulence,
abscess, fibrin coagulation,
endocarditis
The proliferation of pathogenic micro-organisms has to be fought for
3
the physiologic impact to the human health, while non pathogenic
micro-organisms have to be controlled for the visual, olfactory and
tactile effects produced by their metabolism.
The textile materials, on which source of nutrients are present (food
contamination, oil, fat, protein, sugar, skin secretions like sweat and
sebum etc.) become a medium for a rapid multiplication of microorganisms.
Many bacterial colonies produce, in their metabolism,
coloured pigments that protect them against light and UV radiation.
In fig. 1 some colouring pigments, synthesized by different bacteria,
are reported:
Fig. 1
These substances cause colouring of textiles through adhesion to the
surface. The pigments attached to the fibre cannot be adequately
4
removed by normal washing and, as time passes, colour stains firmly
bond to the textile with no possibility of removal, even after repetitive
washings. In some cases, according to the type of fibre material and
attached pigment, only bleaching agents can be helpful, but it is quite
difficult remove the pigment even by the oxidation and reduction
reactions of the bleaching process.
In their growth on a fibre, micro-organisms can produce volatile
compounds of unpleasant odour as decomposition by-products of their
feeding. Spilled foods and drinks, dirt, dust, organic stains, secretions
from the human body like sweat and sebum are decomposed from
bacteria with a production of bad smelling components like : fatty
acids (acetic, propionic, butyric, valerianic, caproic), n-methylamines,
ammonia, aldehydes, sulfides, mercaptans, aromatics and lactones.
Other micro-organisms transform the human steroid hormones in foul
ketones and steroids with the same odour of urine.
3) – Bio-active fibres.
A general term that is adopted to indicate the textile fibres with activity
against micro-organisms growth is “bio-active fibres”. A distinction can
be made according to the possible end-uses: hospital uses, home textiles,
carpets, furnishing, mattress and pillows fillings, air-liquid filters, nonwovens,
protective clothing, sportswear etc. Each of these application
fields will demand a different bioactivity performance from the fibre.
Man-made antibacterial fibres are manufactured by two basic methods:
the first is kneading antibacterial additive during the spinning stage and
the second is an after-treatment method in which an antibacterial agent
solution is used.
In the mixed spinning technology, the antibacterial agent is supplied
5
into the polymer stream before the spinneret or blended into the
spinning polymer feeding. The additive characteristics have to be
compatible with spinning conditions (e.g. particle diameter, heat and
chemical stability, no degradation interactions with polymer, lack of
adverse effects on fibre quality). A reserve of antibacterial additive is
englobed into the fibre and, after migration to the surface, it can
practise its bioactivity against micro-organisms.
In the post-process finishing technology, the most common techniques
to apply antibacterial agents are: spraying, immersion, padding and
coating. The textile surfaces are often treated in the final dyeing and
finishing stages of their manufacturing process. Antibacterial agent is
linked to the surface through physical bonds or anchored by a crosslinking
on the fibre. The most used additives are based on organic
compounds like halogenated salicylic acid, anilides, organotin
compounds, quaternary ammonium compounds, organosilicon
quaternary ammonium salts, and quaternary ammonium sulphonamide
derivatives . Since most of them are highly water soluble and weakly
anchored to the fibre surface, they have to be constantly reapplied.
According to the manufacture technology and the antimicrobial agent
nature, the antibacterial fibres can exhibit two kinds of bioactivity
mechanism: an elution mechanism and a non-elution mechanism. In the
first the additive gradually migrates out from the fibre to the solvent
external medium, while in the second mechanism it does not dissolve
out. Although, sometimes, the two kinds of mechanism coexist in the
antimicrobial activity of a bioactive fibre, generally, one of them is the
predominant.
4) – Antibacterial activity tests .
6
Antibacterial activity of bioactive fibres is not immediately evident, but
it can be evaluated by opportune test methods. Since the early
appearance of bioactive fibres, several standard methods have been
defined and, at the moment, there is not a unique test protocol that is
suitable for all the sorts of the antibacterial fibres. Each of the existing
methods has its own approach and application field, so that, if two of
them are adopted to characterize the same antimicrobial textile, they
often show opposite results.
A first overall classification is carried out on the basis of the kind of
the evaluation of the micro-organism population reduction: quantitative
and qualitative. In the quantitative methods the number of bacteria, still
living after an opportune contact time, is counted. Besides, the
quantitative evaluation can be differentiated further in other two classes
according to the main test conditions. For example, a small amount of
liquid culture medium is used to cover a specimen in the static method
ATCC 100, while the fibre specimen is immersed in a larger amount of
liquid culture when the dynamic Shake Flask Test Method is carried
out.
In the qualitative methods the test specimen and an untreated control
are pressed into intimate contact with an agar culture medium inoculated
with the test bacteria solution. If antibacterial activity is present, it will
be possible observe a clear zone around the treated sample comparing to
the zone of bacterial growth around and over the untreated control
sample after the same contact time.
These qualitative methods provide a formula to measure the inhibition
zone width, but this is a qualitative evaluation and it can not be
considered as a quantitative indication of the antibacterial activity.
The most important antibacterial activity test methods, with their main
7
features, are listed in Tab. 2
Tab. 2
Method Name Origin Evaluation Suitability
AATCC 100/1988-98
USA Quantitative
Textiles treated with
antibacterial finishes.
Hydrophilic fibres
AATCC 147/1988-93 USA Qualitative Textiles treated with
fast migrating/leaching rate agents
SN 195924/1983 SWITZ. Quantitative Hydrophilic fibres
SN 195920/1983 SWITZ. Qualitative Textiles treated with
fast migrating/leaching rate agents
AFNOR XP G 39010: 99 FRANC
E
Quantitative Textiles treated with migrating agents
SHAKE FLASK TEST
JAPAN
USA
Quantitative Textiles with antibacterial
properties inherent to the
structure
Hydrophilic/Hydrophobic fibres
JIS L 1902-8 (1998) JAPAN Quantitative
and
Qualitative
Textiles treated with
fast migrating/leaching rate agents
The results that these methods can give depend strongly on the
antibacterial additive mechanism of activity and on the hydrophobic or
hydrophilic nature of the bioactive fibre. In each analysis, the
measurement of the activity of a reference sample of nature similar to
the antibacterial fibre but without additive must be carried out.
After the time contact, three cases of bioactivity can present as result
8
of testing a textile:
1) a significant increase of the initial bacteria population
2) an inhibition of the bacteria growth comparing the antimicrobial
product with the control sample for which there is a multiplication of
test bacteria population inoculated at the beginning of the time
contact.
3) a quantitative reduction of the number of test bacteria inoculated at
the beginning of the time contact.
The second and the third cases indicate an antibacterial activity from
the bioactive fibre and the terms used to differentiate the two
performances are biostatic and biocide.

Hygiene Fibres - Antimicrobial Polyester

1) – Introduction. Since the last part of the century an increasing improvement in qualitative standards of human lifestyles has brought to a greater sense of comfort, and cleanliness. People are more and more looking for fresh public living surroundings and a higher level of hygiene in home areas. A wide class of micro-organisms coexists in a natural equilibrium with human body and living environments, but a rapid and uncontrolled multiplication of even non pathogenic microbes can seriously compromise the hygienic and healthy personal standards. Because of their capillary spread in the human living spaces, the textiles have been involved in this research of a growing quality of hygienic living conditions. Actually, several combinations of temperature, humidity and other climate factors added to the presence of dust, soil and fat-stains on the textile surfaces can transform the textiles themselves in an optimal enrichment culture for a rapid multiplication of micro-organisms. In such a case two contemporary effects occur: the first is an uncontrolled proliferation from textile surfaces into the surrounding environment with a consequent increase of bio-burden level and potential health risks or, at least, of discomfort for the unpleasant odours produced by high concentrations of micro-organisms; the second one is the onset of degradation phenomena as colouring and discoloration of the textile fibres. Many efforts have been performed by textile industry with the aim to score two goals: the protection of the living environments and of the textile fibres from an uncontrolled proliferation of microorganisms like bacteria. 2) – Micro-organisms action on textile surfaces. In the broad spectrum of existing bacteria there are pathogenic and non-pathogenic organisms. Both of them can multiply abnormally on the textile surfaces with an accumulation that compromises the hygienic cleanliness. Tab.1 shows some examples of pathogenic and non pathogenic microorganism. Tab. 1 MICRO ORGANISM PATHOGENICIT Y EFFECTS Bacillus subtilis Generally non pathogenic Food spoiling occasionally conjunctivitis Escherichia coli Low pathogenic Food spoiling occasionally urinary bladder infection Klebsiella pnuemoniae Pathogenic Pneumonia, urinary bladder infection Pseudomonas aeuroginosa Pathogenic Multi-infections Proteus vulgaris Low pathogenic Infiammations Staphylococcus epidermidis Low pathogenic Surgical wound infections Staphylococcus aureus Pathogenic Toxic shock, purulence, abscess, fibrin coagulation, endocarditis The proliferation of pathogenic micro-organisms has to be fought for 3 the physiologic impact to the human health, while non pathogenic micro-organisms have to be controlled for the visual, olfactory and tactile effects produced by their metabolism. The textile materials, on which source of nutrients are present (food contamination, oil, fat, protein, sugar, skin secretions like sweat and sebum etc.) become a medium for a rapid multiplication of microorganisms. Many bacterial colonies produce, in their metabolism, coloured pigments that protect them against light and UV radiation. In fig. 1 some colouring pigments, synthesized by different bacteria, are reported: Fig. 1 These substances cause colouring of textiles through adhesion to the surface. The pigments attached to the fibre cannot be adequately 4 removed by normal washing and, as time passes, colour stains firmly bond to the textile with no possibility of removal, even after repetitive washings. In some cases, according to the type of fibre material and attached pigment, only bleaching agents can be helpful, but it is quite difficult remove the pigment even by the oxidation and reduction reactions of the bleaching process. In their growth on a fibre, micro-organisms can produce volatile compounds of unpleasant odour as decomposition by-products of their feeding. Spilled foods and drinks, dirt, dust, organic stains, secretions from the human body like sweat and sebum are decomposed from bacteria with a production of bad smelling components like : fatty acids (acetic, propionic, butyric, valerianic, caproic), n-methylamines, ammonia, aldehydes, sulfides, mercaptans, aromatics and lactones. Other micro-organisms transform the human steroid hormones in foul ketones and steroids with the same odour of urine. 3) – Bio-active fibres. A general term that is adopted to indicate the textile fibres with activity against micro-organisms growth is “bio-active fibres”. A distinction can be made according to the possible end-uses: hospital uses, home textiles, carpets, furnishing, mattress and pillows fillings, air-liquid filters, nonwovens, protective clothing, sportswear etc. Each of these application fields will demand a different bioactivity performance from the fibre. Man-made antibacterial fibres are manufactured by two basic methods: the first is kneading antibacterial additive during the spinning stage and the second is an after-treatment method in which an antibacterial agent solution is used. In the mixed spinning technology, the antibacterial agent is supplied 5 into the polymer stream before the spinneret or blended into the spinning polymer feeding. The additive characteristics have to be compatible with spinning conditions (e.g. particle diameter, heat and chemical stability, no degradation interactions with polymer, lack of adverse effects on fibre quality). A reserve of antibacterial additive is englobed into the fibre and, after migration to the surface, it can practise its bioactivity against micro-organisms. In the post-process finishing technology, the most common techniques to apply antibacterial agents are: spraying, immersion, padding and coating. The textile surfaces are often treated in the final dyeing and finishing stages of their manufacturing process. Antibacterial agent is linked to the surface through physical bonds or anchored by a crosslinking on the fibre. The most used additives are based on organic compounds like halogenated salicylic acid, anilides, organotin compounds, quaternary ammonium compounds, organosilicon quaternary ammonium salts, and quaternary ammonium sulphonamide derivatives . Since most of them are highly water soluble and weakly anchored to the fibre surface, they have to be constantly reapplied. According to the manufacture technology and the antimicrobial agent nature, the antibacterial fibres can exhibit two kinds of bioactivity mechanism: an elution mechanism and a non-elution mechanism. In the first the additive gradually migrates out from the fibre to the solvent external medium, while in the second mechanism it does not dissolve out. Although, sometimes, the two kinds of mechanism coexist in the antimicrobial activity of a bioactive fibre, generally, one of them is the predominant. 4) – Antibacterial activity tests . 6 Antibacterial activity of bioactive fibres is not immediately evident, but it can be evaluated by opportune test methods. Since the early appearance of bioactive fibres, several standard methods have been defined and, at the moment, there is not a unique test protocol that is suitable for all the sorts of the antibacterial fibres. Each of the existing methods has its own approach and application field, so that, if two of them are adopted to characterize the same antimicrobial textile, they often show opposite results. A first overall classification is carried out on the basis of the kind of the evaluation of the micro-organism population reduction: quantitative and qualitative. In the quantitative methods the number of bacteria, still living after an opportune contact time, is counted. Besides, the quantitative evaluation can be differentiated further in other two classes according to the main test conditions. For example, a small amount of liquid culture medium is used to cover a specimen in the static method ATCC 100, while the fibre specimen is immersed in a larger amount of liquid culture when the dynamic Shake Flask Test Method is carried out. In the qualitative methods the test specimen and an untreated control are pressed into intimate contact with an agar culture medium inoculated with the test bacteria solution. If antibacterial activity is present, it will be possible observe a clear zone around the treated sample comparing to the zone of bacterial growth around and over the untreated control sample after the same contact time. These qualitative methods provide a formula to measure the inhibition zone width, but this is a qualitative evaluation and it can not be considered as a quantitative indication of the antibacterial activity. The most important antibacterial activity test methods, with their main 7 features, are listed in Tab. 2 Tab. 2 Method Name Origin Evaluation Suitability AATCC 100/1988-98 USA Quantitative Textiles treated with antibacterial finishes. Hydrophilic fibres AATCC 147/1988-93 USA Qualitative Textiles treated with fast migrating/leaching rate agents SN 195924/1983 SWITZ. Quantitative Hydrophilic fibres SN 195920/1983 SWITZ. Qualitative Textiles treated with fast migrating/leaching rate agents AFNOR XP G 39010: 99 FRANC E Quantitative Textiles treated with migrating agents SHAKE FLASK TEST JAPAN USA Quantitative Textiles with antibacterial properties inherent to the structure Hydrophilic/Hydrophobic fibres JIS L 1902-8 (1998) JAPAN Quantitative and Qualitative Textiles treated with fast migrating/leaching rate agents The results that these methods can give depend strongly on the antibacterial additive mechanism of activity and on the hydrophobic or hydrophilic nature of the bioactive fibre. In each analysis, the measurement of the activity of a reference sample of nature similar to the antibacterial fibre but without additive must be carried out. After the time contact, three cases of bioactivity can present as result 8 of testing a textile: 1) a significant increase of the initial bacteria population 2) an inhibition of the bacteria growth comparing the antimicrobial product with the control sample for which there is a multiplication of test bacteria population inoculated at the beginning of the time contact. 3) a quantitative reduction of the number of test bacteria inoculated at the beginning of the time contact. The second and the third cases indicate an antibacterial activity from the bioactive fibre and the terms used to differentiate the two performances are biostatic and biocide.

Organic Cotton - facts

There has been some confusion about what really are natural fibers used in textiles. In some people’s opinion, natural fiber clothing is the same as organic clothing. In conversations, “natural clothing” is sometimes used to refer to organic clothing because the clothing is completely natural and was not grown with any toxic chemicals nor manufactured using toxic chemicals. But natural fiber clothing simply refers to clothing made from fibers found in nature, such as cotton, wool or hemp, which may not be grown or manufactured under conditions which would allow them to be certified as organic. Natural fibers fall into three main groups: vegetable fibers which come from plants; protein fibers, which come from the wool and hair of animals; and the strong elastic fibrous secretion of silkworm larvae in cocoons which is used to create silk. The main ingredient in all vegetable fibers is cellulose, a carbohydrate found in all plant life. The most common natural fibers used to make clothing are cotton, hemp, ramie, linen, lyocell / Tencel, wool, and silk. This article on cotton is the first in a series that examines each of these natural fibers in their journey from the field to the fashion runway as they journey to rise to ecofashion stardom or sink into conventional toxic Margarittaville. Cotton – hero or villain? When we think about global warming, growing cancer rates, deepening poverty in some of the world’s poorest countries, and even increasing chemical sensitivities, our clothes closets are probably not the first villain that comes to mind, but our clothes can be a significant, quiet co-conspirator. Cotton evokes images of white, fluffy purity and many people think of cotton as being a natural, pure fabric. Cotton is a wonderfully versatile and globally important fiber that is used for a vast variety of fiber and food products, making it one of the most widely traded commodities on earth. Versatility, softness, breath-ability, absorbency, year-round comfort, performance, and durability are just a few of the qualities that have earned cotton its popular status. Due to its unique fiber structure which can absorb up to 27 times its own weight in water, cotton breathes and helps remove body moisture by absorbing it and wicking it away from the skin. Not only is cotton the most popular and best selling fabric in the world, due to its huge commercial value, cotton also represents an essential component of foreign exchange earnings for more than fifty countries. The value and reach of cotton extends far past the fashion runway. But, the global cotton industry has a worldwide Dark Side of which most of us are not aware as we fill our shopping bags with inexpensive cotton shirts from major clothing stores. The simple act of conventionally growing and harvesting the one pound of cotton fiber needed to make a T-shirt takes an enormous and devastating toll on the earth’s air, water, and soil that impacts global health. Also, policies and practices within the cotton industry from crop subsidies to garment sweatshops create poverty and misery that stretch around the world. Cotton industry trade organizations such as Cotton Incorporated spend millions and millions of dollars attempting to convince American consumers of the hoax that conventional chemical cotton is pure and friendly to the health of the wearer. Let’s take a tour of the major steps in the journey of cotton from field to fashion. At each step, we will compare the processes for conventional cotton and for organic cotton. Ready? There is a general four-step process to turn a cotton seed into cotton apparel. Planting and growing Harvesting Cleaning or “ginning” of the cotton boll Manufacturing The manufacturing step consists of several important activities: Spinning the cotton fibers to create yarn, Weaving or knitting to create bolts of cotton fabric, Fabric dyeing, Finishing process to create the smooth fabric, Cutting and sewing of garment for consumers. Step 1. Planting & Growing. The cotton fiber and seed grow in a pod called a boll which develops from the flowers of cotton plants and opens when the cotton plant is mature. After cotton is harvested, the cotton boll is then taken to a gin which removes the fiber from the seed. The fiber is then packaged into bales weighing almost 500 pounds. The seed is pressed into cottonseed oil and used in processed foods for people or it is fed to livestock. A sample of cotton fiber from each bale is tested for strength, length and color. Cotton spinning mills buy the cotton bales based on these qualities, and then process the fiber into spun yarn. A textile mill will process the yarn into woven or knitted fabric. The fabric will then be transported to a garment manufacturing shop (often in a low wage region or country) where it will be cut and sewn into the final garment. Cotton may be dyed at the fiber stage, the yarn stage, the fabric stage, or the final garment stage. Conventionally grown cotton. Farmers in the United States apply nearly one-third of a pound of chemical fertilizers and pesticides for every pound of cotton harvested. When all nineteen cotton-growing states are tallied, cotton crops account for twenty-five percent of all the pesticides used in the U.S. Some of these chemicals are among the most toxic classified by the U.S. Environmental Protection Agency. In developing countries, where regulations are less stringent, the amount of herbicides and insecticides and their toxicity is often greater than in the U.S.

Perspective, just 2.4% of the world's arable land is planted with cotton yet it accounts for 24% of the world's insecticide market and 11% of global pesticides sales, making it the most pesticide-intensive crop grown on the planet. The pesticides used by farmers not only kill cotton pests but also decimate populations of beneficial insects such as ladybugs and parasitic wasps. Because their natural enemies have been eradicated, these target insects, which were once only minor nuisances for farmers, become greater problems and ever-increasing quantities of toxic chemicals must be sprayed to keep them in check. Farmers then become stuck on what is known as the ‘pesticide treadmill’.
Pesticides not only disrupt the balance of nature in the field, but also harm people who come in contact with them. According to the Organic Consumers Association, the use of pesticides, which includes insecticides, herbicides and fungicides, for conventional cotton production has created serious problems for human health and the environment in all cotton-growing regions worldwide.
The health of our planet has also been adversely affected by pesticides. The pesticides and synthetic fertilizers used on cotton routinely contaminate groundwater, surface water and pollute the water we drink. Fish, birds and other wildlife are also affected by the movement of these chemicals through the ecosystem. Many of these problems have been documented by the Pesticide Action Network North America.
In 1995, pesticide-contaminated runoff from cotton fields in Alabama killed 240,000 fish.
It is estimated that pesticides unintentionally kill 67 million birds each year.
14 million people in the U.S. are routinely drinking water contaminated with carcinogenic herbicides and 90 percent of municipal water treatment facilities lack equipment to remove these chemicals.
The growth of industrial agriculture and consolidation in the seed industry has replaced hundreds of cotton varieties with only a handful. The practice of planting thousands of acres all of the same variety is known as monoculture and has left the crop extremely vulnerable to pests and diseases which also forces cotton farmers onto the “chemical treadmill.” Conventional farmers using toxic chemicals have found themselves embroiled in an endless battle with crop pests. Over 500 species of insects, 180 weeds and 150 fungi have developed resistance to the chemicals used to kill them off. Agricultural biotech companies continually develop new products to keep up with this resistance and keep farmers on the ‘chemical treadmill’.
Organically grown cotton. Working with rather than against nature is the guiding principle behind organic farming. Organic farmers use biologically-based rather than chemically dependent growing systems to raise crops. While many conventional farmers are reacting to the ecological disorder created by monocultures, organic farmers focus on preventing problems before they occur.
By focusing on managing rather than completely eliminating troublesome weeds and insects, organic farmers are able to maintain ecological balance and protect the environment. Organic cotton is now being grown in more than 18 countries worldwide. In the United States, approximately 10,000 acres of organic cotton were planted in 1998 in the Mid-South, Texas and California.
The Soil: Organic Farming starts with healthy soil. The soil is seen as a living system and not simply a growing medium for plants. Compost, efficient nutrient recycling, frequent crop rotations and cover crops replace synthetic fertilizers to keep the soil healthy and productive.

Weed Control: Organic Farmers have many options to control weeds including: hoes and other mechanical weeding implements, crop rotations, planting several crops together (intercropping), more efficient use of irrigation water, the use of mulches, and even adjusting the planting dates and densities of their crops.
Pest Control: By encouraging biological diversity, farmers create conditions which reduce the likelihood of any insect, bird or mammal doing any major damage to their crop. To control pests, organic farmers may use beneficial predator insects, crop rotations, intercropping, and biological pesticides such as neem oil.
Step 2. Harvesting.
Conventionally Harvested Cotton. After the toxic debacle of the growing season, the chemical woes only continue. During harvesting, herbicides are used to defoliate cotton plants to make picking easier. The global consequences are that chemicals pollute ground water and rivers with potentially carcinogenic compounds. Large harvesting machinery compacts the ground reducing soil productivity.
Organic Harvested Cotton. Organic cotton is often hand picked, especially in developing countries, without the use of defoliants, machinery, or chemicals. Hand picking also means less waste.
Step 3. Cleaning & Ginning. So far, we have journeyed only to the end of the cotton field, but the story doesn’t end there. Manufacturing cotton fiber into fabric and garments consists of several major processes – cleaning, spinning, knitting or weaving, dyeing, cutting and assembly, finishing, and cleaning.
Before cotton fiber can be manufactured from cotton plants, several cleaning steps are required. After the plants have been processed at a cotton gin, the product is distributed to fiber producers. The fiber manufacturer further removes plant material and other debris by dividing and carding the lint. The waste from this process is a mixture of stems, leaves, soils, and lint.
Cotton is also an important food source for humans and animals. Cotton is comprised of 40% fiber and 60% seed by weight. Once separated in the gin, the fibers go to textile mills, while the seed and various ginning by-products are used for animal feed and for human food, mostly in the form of cottonseed oil. Cottonseed, which is rich in oil and high in protein, is a common ingredient in cookies, potato chips, salad dressings, baked goods, and other processed foods.
Conventional Cotton By-Products. With conventionally grown cotton, the pesticide residues from the cottonseeds concentrate in the fatty tissues of these animals, and end up in meat and dairy products.
Organic Cotton By-Products. Organically grown cotton can be used to produce organic food products for people and animals. Organic cotton is important not just in the clothing chain but also in the food chain.
Step 4. Manufacturing – Spinning, Weaving, Knitting, Dying, & Finishing
Conventionally Manufactured Cotton. Conventionally manufactured cotton must be chemically processed to become the soft fiber that consumers love. Although cotton is one of the most heavily sprayed crops in the United States, much of the pesticide and herbicide is bleached out or washed away during the manufacturing process, but a variety of toxic chemicals, oils, and waxes are used to manufacture, knit and weave convention cotton fabrics. The chemical residues of these processes constitute the major sensitivity problems experienced by people suffering from Multiple Chemical Sensitivities.
Only in the spinning process where cotton fibers are spun into yarn is cotton untouched by chemicals or oils. After spinning, the yarn receives a polyvinyl alcohol sizing to make the yarn easier to weave. After weaving, the fabric is then bleached. Half the companies in the U.S. use hydrogen peroxide, but half still use highly toxic chlorine. Companies outside the >U.S. and Europe, where most garments are produced, are more likely to use chlorine. The sizing is then removed from the fabric with a detergent. Next, it is washed or “scoured” with sodium hydroxide. Finally, it is piece-dyed, often with formaldehyde-fixing agents. An additional washing is needed to attempt to remove the formaldehyde-fixing agents.
The last step is finishing and this is where many chemical sensitivity problems begin. A urea-formaldehyde product which cross-links molecules is routinely applied to all United States cottons to reduce shrinkage and wrinkling. Cotton is a fiber designed by nature to absorb, and heat is used to lock finishes into the fiber. When heat is applied, this molecule expands and becomes permanently bound in the fiber. That is why it cannot be washed or dry cleaned out.
“Pure finish” indicates that nothing has been applied to the fabric at this point, but this does not always guarantee that people who are chemically sensitive will be able to wear the garment. Detergents and softeners are heavily used in making fabrics, and some of these will leave a residue that will never wash out completely.
Knitted fabric goes through similar processes. To be knittable, yarn must be waxed and oiled. The knit fabric is then washed in detergents and softeners. An anti-curl chemical is added to the wash for all jerseys and many fleeces. Knit goods that are piece-dyed after knitting follow the same course as woven fabrics. Yarn-dyed knits are washed, framed, steamed, and finished with heat and, usually, formaldehyde resin.
Sweaters and some circular knits are just washed with detergent and softeners and tumble-dried to remove oils and to reduce shrinkage. No finish is put on them, but again their wearability depends on the chemicals used to wash and soften them. The low-foam industrial detergent Aresolve is one of the worst offenders around. As with woven fabrics, heat is used as part of the processing and can actually lock chemicals into the fiber.
It is impossible to knot yarn without waxing and oiling and the oil must be washed out with some kind of detergent. Jerseys must be de-curled to lie flat on a table for cutting. Traditional cotton fabrics are often scoured, washed, and bleached with chlorine, APEO (alkylphenoloxylate, a hormone disrupter), EDTA (ethylenediamine tetra-acetate which binds with heavy metals in rivers and streams), and volatile organic compounds (VOCs) that react with sunlight to form ground-level ozone. These toxic chemicals are slow to biodegrade and recent research has shown links to the production of “probable” carcinogens.
The dyeing and printing of conventional cotton fabrics often use compounds of iron, tin, potassium, VOCs and solvent-based inks containing heavy metals, benzene, and organochlorides that require large quantities of water to wash out the dye residues. This waste water is polluted by these heavy metals. The toxic residues found in the waste water can cause problems of the central nervous system, respiratory system, and skin, as well as head-aches, dizziness, and eye irritations.
“Finishing” is the final processing step for many conventional cotton garments to create easy care clothing that is soft, wrinkle-resistant, stain and odor resistant, fireproof, mothproof, and anti-static. Chemicals often used for finishing include formaldehyde, caustic soda, sulfuric acid, bromines, urea resins, sulfonamides, halogens, and bromines. The resulting waste water has a high acid content. Residual chemical traces on the fabric can cause burning eyes, nose, and throat, as well as difficulties with sleep, concentration, and memory and they can increase susceptibility to cancer. The emissions from these residual chemicals in conventional cotton fabric increase with temperature. Unless clothes are 100 percent organic, you should always wash new clothes or bedding first before wearing or putting on the bed. That "new" smell is a potent mixture of chemicals such as formaldehyde and urea resins that can be reducedS through repeated washings.
Some imported clothes are now impregnated with long-lasting disinfectants that can be identified by the smell alone. These disinfectants are very hard to remove and the healthiest action is to not buy the clothes.
Manufacturing organic cotton. At each manufacturing step, organic clothing manufacturers do not add petroleum scours, silicon waxes, formaldehyde, anti-wrinkling agents, chlorine bleaches, or other unauthentic materials. Natural alternatives such as natural spinning oils that biodegrade easily are used to facilitate spinning; potato starch is used for sizing; hydrogen peroxide is used for bleaching; organic color grown cottons and low-impact dyes and earth clays are used for coloration; and natural vegetable and mineral inks and binders are used for printing on organic cotton fabric. These natural alternatives are used to reduce and eliminate the toxic consequences found in conventional cotton fabric manufacturing.
Cultivating Poverty Globally. Conventional cotton is also involved in a further global social tragedy: the devastating economic impact on some of the poorest people and countries in the world caused by subsidized cotton in the U.S. and the proliferation of garment sweatshops located in developing countries. An unfortunate combination of large U.S. subsidies to U.S. cotton growers and corporate greed in outsourcing garment manufacturing to sweatshops has created economic hardship for cotton farmers and garment workers throughout some of the world’s poorest countries and most vulnerable people in the world.
Cotton is a global crop native to Southern Africa and South America and is grown on over 90 million acres in more than 80 countries worldwide. The millions of tons of cotton produced each year account for 50% of the world’s fiber needs with wool, silk and flax together accounting for only 10%. Besides being the world’s most popular fabric, cotton is widely used as livestock feed and in food products such as salad dressing and crackers. The United States is the second largest cotton producer in the world after China and the world’s largest cotton exporter. Approximately 19 million bales of cotton were grown in 18 U.S. states. A major factor in cotton’s popularity with American growers and exporters is that the U.S. Government heavily subsidizes American growers for growing cotton. The result is that American growers can sell their cotton cheaply because they are also receiving generous payments directly from the U.S. Government which paid U.S. cotton farmers $2.3 billion in 1999 and $2.06 billion in 2001, according to the Department of Agriculture.
American cotton subsidies are destroying livelihoods in Africa and other developing regions. By encouraging over-production and export dumping by U.S. cotton growers, these subsidies are driving down world cotton prices on an inflation-adjusted basis to their lowest levels since the Great Depression. While American cotton barons get rich on government subsidies, African farmers suffer the consequences. Meanwhile, America’s share of world cotton exports has risen from under 20% in 1999 to more than 40% in 2004, estimates the International Cotton Advisory Committee. Estimates indicate that United States cotton output would have fallen by 29% between 1999 and 2002, and world prices would have risen by 12.6% if it were not for America's offending subsidies.
Many cotton growing countries around the world such as Brazil and Central and West African countries, including Burkina Faso, Benin and Mali, are heavily dependent on cotton for the bulk of their export earnings. More than 10 million people in Central and West African countries depend directly on cotton production with many more millions being indirectly affected. According to the World Bank, these African regions are among the lowest-cost producers of cotton. Yet despite this comparative advantage, they are losing world markets and their farmers are suffering rising poverty. They have been hit hard by sharp falls in cotton prices in recent years and contend that U.S. subsidies distort prices and harm competition. Recent rulings by the World Trade Organization find that the U.S. has been illegally using domestic cotton subsidies to bolster its dominant position in the market.
The scale of government support to America’s 25,000 cotton farmers is staggering, reflecting the political influence of corporate farm lobbies in key states. Every acre of cotton farmland in the U.S. attracts a subsidy of $230. In 2001/02 farmers reaped a bumper harvest of subsidies amounting to $3.9billion – double the level in 1992. To put this figure in perspective, America’s cotton farmers receive more in subsidies than the entire Gross Domestic Product (GDP) of Burkina Faso – a country in which more than two million people depend on cotton production. Over half of these farmers live below the poverty line.
The small size of the Central and West African cotton producing countries and their high level of dependence on cotton magnify the effect of US policies. The economic losses inflicted by the U.S. cotton subsidy program far outweigh the benefits of the financial aid that they receive from the U.S. Mali, for example, received $37million in U.S. aid in 2001 but lost $43million as a result of lower cotton export earnings due to depressed cotton prices and competition from subsidized U.S. cotton growers.
Notwithstanding constant references to the ‘family farm’ on the part of U.S. policy makers, farm subsidies are designed to reward and encourage large-scale, corporate production. The largest 10% of the U.S. cotton farms receive three quarters of total cotton subsidy payments. One of the biggest subsidy gatherers in the U.S. is Tyler Farms, an Arkansas-based corporation that controls 40,000 acres – an area almost as large as the District of Columbia. The farm also grows corn, rice, sorghum, and oilseeds. All of these crops generate a healthy return by way of government subsidies. However, cotton is Tyler Farms’ major subsidy crop, generating almost $6million in 2001. This one farm receives subsidies from the U.S. Government equivalent to the average income of 25,000 people in Mali.
When measured by cost per acre, farmers in Africa are among the most cost-efficient in the world, despite climatic uncertainties, limited infrastructure, and high levels of poverty. On a level playing field, they could compete with U.S. cotton farms. What they cannot compete with is U.S. cotton farms selling cotton on international markets at prices that bear no relation to the costs of production, courtesy of corporate welfare checks underwritten by the world’s most powerful treasury.