Faerben_und_AusruestenGB.pdf

Dyeing andFinishing ofWoven andKnitted Fabrics

Reg. NO 3083

Dorlastan Dyeing and Finishing of Woven and Knitted Fabrics

Asahi Kasei Spandex Europe GmbH41519 Dormagen, Germany

Contents Page

1. From Greige Goods to Finished Article 3

1.1 Relaxation 4

1.1.1 Relaxation on Steaming Tables 4

1.1.2 Relaxation by Steaming at the Tenter Feed End 5

1.1.3 Relaxation by Means of Hot Water 5

1.2 Hot-air Setting 5

1.3 Wet Treatment 5

1.3.1 Scouring 5

1.3.2 Dyeing Method 6

1.4 Aftertreatment 7

2. Article Characteristics and their Influences on the Procedure 7

2.1 Raschel Knits 7

2.2 Warp-knits 8

2.3 Knits 10

2.3.1 Flat Knits 10

2.3.2 Circular Knits 10

2.4 Wovens 12

3. Bleaching, Fluorescent Whitening and Dyeing 13

3.1 Dorlastan/Polyamide 13

3.1.1 Scouring 13

3.1.2 Fluorescent Whitening 13

3.1.3 Dyeing 14

3.2 Dorlastan/Polyester 15

3.2.1 Scouring 16

3.2.2 Fluorescent Whitening 16

3.2.3 Dyeing 17

3.3 Dorlastan/Wool 18

3.4 Dorlastan/Cotton 19

Appendix 24


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Edition: 01: 07/94 02: 09/98 03: 01/04 04: 07/04 05: 04/05 06: 03/06

Published by and responsibility Approval

gez. ppa. Schmidt gez. Nahl

Marketing Dorlastan Geschäftsführer

1.From Greige Goods to Finished Article

The characteristic features of an elastic fabric are extensibility and elasticrecovery. They are achieved with the help of elastane threads which areincorporated in stretched condition during greige fabric production. In the courseof the subsequent storage and finishing, the greige fabric with the elastanethreads is relaxed and becomes compressed, and thus obtains its elasticity. Theamount of stretch of an elastic fabric depends on the fabric structure formed bythe non-elastic yarns, which in turn is strongly influenced by the processingtechnique (circular knit, warp knit, etc.). The elastic recovery is determined by the retractive force of the stretched elastane threads and by the resistance of thecompressed textile structure.

Greige fabric is not suited for making-up, so the appropriate conditions forachieving the desired finished article properties must be created prior to this step.They include color, luster and touch for both, elastic as well as non-elastic fabrics.Elastic fabrics must additionally provide reoverable stretch. To meet theserequirements, suitable finishing processes must be chosen that are able toproduce finished articles of nice appearance and hand with the desired technicaland elastic properties.

Greige fabric should always be delivered to the finisher on rolls because manyqualities show a strong tendency to shrink if plaited down, which may result inirreversible crease and lay mark formation. Moreover, unrelaxed greige goodsshould not be stored for a long time in rolled-up, and particularly tightly rolled-up,condition because such storage may lead to moiré formation.

If stored in warm and humid condition, elastic greige goods, especially elasticknits, may start to become denser before finishing is even begun. As aconsequence, fabric width and m2-weight may change. To enable the finisher totake such circumstances into account, the greige good supplier must provide himwith all the details of manufacture.

If such details are not available to the finisher, as it frequently happens, he shouldfind out about the shrinkage by preliminary tests, especially if he is not familiarwith the good and works with the fabric for the first time. A good method todetermine the maximum density of any fabric is to boil a piece of the greige cloth and subsequently dry it tension-free, e.g. in a tumbler. Such treatment willcause any fabric to shrink extremely as it would never do in normal processingprocedures. The degree of shrinkage tells the finisher which are the most suitablefinishing procedures for the respective fabric.

Regardless whether a greige fabric containing elastane displays a strong naturaltendency to shrink or whether the shrinkage must be enhanced, the customer’srequirements must always have first priority. The maximum shrinkage must beappropriate to reach the desired m2-weight, running length and width in thefinished product. If this is achieved after relaxation, and there is no other reasonto apply it, you may well do without heat setting (e.g. in case of raschel powernets).


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If however, the dimensions of the relaxed fabric does not meet the customer’srequirements for width and weigth, or if the edges show excess curl (e.g. withwarp knits) heat setting is inevitable.

Another important point in this context is dimensional stability (i.e. low shrinkagevalues). If hot air fixation is applied to influence m2-weight and stretch, it must besufficient to create this stability.

Once a greige good has been relaxed and possibly stabilized, it must be ensuredthat the resulting properties are not unnecessarily endangered or even lost duringfurther processing. This means:

– Tensions in longitudinal direction should be kept as low as possible– Wet treatment temperatures should not exceed 100°C (except for articles

containing polyester)– Chemicals that impair the elastic properties of Dorlastan should not be

applied– The combined strain resulting from chemicals, time, temperature and tension

should be reduced to a minimum.

Like other fabrics, elastic fabrics must be subjected to all the standardoperations of finishing, such as scouring, setting, dyeing, dressing and possiblyraising, shearing or decatizing. In addition, however, further measures arenecessary to develop, stabilize, and maintain or reverse the stretch effect

You find a description of the various operations involved in the finishing of elasticfabrics in the following sections.

1.1 Relaxation

The greige fabric can be relaxed by means of steam or hot water. For thispurpose, the fabric must be fed to the machine with low tension so that it canshrink freely at least to the desired cloth density.

1.1.1 Relaxation on steaming tables

This method is widely used. The shrinkage is largely determined by the articleitself, but can be controlled to a certain extent via the steam amount and thefeeding speed. The greige fabric is put onto the steaming table with overfeed,taken off tensionless and then rolled up. If the fabric has a strong tendency tocurl at the edges (e.g. warp knits) or if a prescribed width must be achieved, it isrecommended to use steaming tables with lateral spiked chain guides.


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1.1.2 Relaxation by Steaming at the Tenter Feed End

Relaxation by steaming at the tenter feed end allows greater control of the clothshrinkage by means of overfeed and width adjustment of the tenter frame. A special advantage of this method is the constant fabric width over the entirebatch, so that the fabric can be rolled up evenly afterwards. This is an essentialprerequisite for a subsequent treatment in the dyeing beam.

When steamed in the tenter feed an elastic fabric does not shrink as much inwidth as it would during preshrinking in other equipment because of the heavyweight of the sagging fabric. The greige fabric should be fed to the tenter viaroller drive and not be drawn from the roll; if it is drawn from the roll, thelongitudinal shrinkage will increase from the beginning to the end of the batchbecause of the decreasing roll weight and the diminishing take-off tension goingwith it, i.e. the longitudinal shrinkage may vary over the entire batch length. Thenormal tenter temperature for shrinking ranges from 100–140°C. If shrinking andhot air setting are combined, the processing temperate is approximately185–195°C.

1.1.3 Relaxation by Means of Hot Water

Scouring and shrinking can be combined in low-tension open-width washers atoperating temperatures between 60 and 95°C.

1.2 Hot air setting

Hot air setting must be applied if a fabric’s shrinking tendency exceeds thecustomer’s specifications with regard to m2-weight, running length and clothwidth. In addition, it has an area stabilization effect that can be used to eliminateor to reduce undesired edge curling.

How much setting is required is highly dependent on the article, so no generalrules can be established. Since it is essential to maintain the elastic properties ofthe fabric, the setting conditions should not be more severe than necessary, butsufficient to meet the customer’s requirements and to achieve good shrinkagevalues. Appropriate setting conditions can easily be determined by preliminarytests and will include exposure times ranging from 25 to 60 seconds. The settingtemperature is determined first of all by the type of Dorlastan that is used.Polyether = 192–196°C, polyester = 185–190°C.

1.3 Wet Treatment

1.3.1 Scouring

Optimal preparatory treatment that guarantees good reproducibility of the entireprocess includes the thorough removal of both the silicone lubricant required forthe processing of elastane and the lubricants of the non-elastic fiber componentsin order to avoid mutual reactions of the two lubricant types. Diadevin®DSP hasproven a suitable agent for this purpose.


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Whether scouring is performed in open-width or rope form depends primarily onthe article, but also on what equipment is available.

1.3.2 Dyeing Method

Selection of the dyeing method is determined by the article’s tendency to crease.

Fabrics that are prone to creasing require open-width dyeing. This technique canbe performed on jig or beam dyeing machines.

Jig dyeing machines with sufficient controls to operate at very low tension, andcompensate as the fabric shrinks during dyeing are required. If an appropriatelow tension is guaranteed for the fabric feed, the jig is an economic solution fordyeing stable fabrics that do not curl at the edges (e.g. wovens). High qualitiescan be produced, if water pockets resulting from unnecessary standstills of thejig are avoided, and the exposure time and treatment temperature are limited tothe required levels. Water pockets disturb the smooth running of the fabric andeasily cause creasing. Once the pockets have formed, crease formation can onlybe avoided by increasing the fabric tension, which leads inevitably to lowerqualities.

By the treatment on the jig the elastic material is stretched. If the resultingelongation is only slight, it can well be reversed during the subsequent drying by an appropriate overfeed. However, increased fabric tension and extendedexposure times at high temperatures as they are often required with dark colorssometimes lead to greater elongations, which cannot always be compensated for by the tenter overfeed during intermediate drying. The dyed fabric may beslightly longer compared to the relaxed greige fabric and may have a lower m2-weight combined with less stretch. To avoid these negative effects beamdyeing is often preferred.

For beam dyeing, the elastic fabric must be subjected to optimal prior relaxationand, if necessary, also to hot setting. These measures are necessary to preventthe fabric shrinking in width in the autoclave resulting in the lateral perforations of the dyeing beam being uncovered. At the tenter feed end, the fabric is evenlywound on the dyeing beams at constant wounding tension. During the wholedyeing process, the liquid in the autoclave should circulate only from the insideto the outside, the differential pressure should be maintained at 0.1–0.2 bar byreducing the liquid flow rate, and the liquid temperature should be increasedand/or decreased only slowly.

In contrast to jig dyeing, dyeing on the beam always involves a risk of moiréformation, especially with dark colors. The above mentioned even woundingtension, slow temperature change, and the use of dyeing beams of largediameters adequately wrapped with non-dyeing leader cloth help to reduce this risk to a minimum.

Goods that are not prone to creasing can be winch beck dyed, overflow dyed orjet dyed in rope form.


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1.4 Aftertreatment

There are numerous possibilities for aftertreatment. Selection of the techniquedepends on the composition of the article and the customer’s specifications. This will not be covered in detail in this general description.

2. Article Characteristics and their Influence on the Procedure

2.1 Raschel Knits

Compared to other elastic knit fabrics most types of raschel fabrics are relativelystable, they have no or little tendency to curl at the edges, their shrinkingtendency is sufficient and reproducible, and rarely exceeds the desired level.Raschel fabrics shrink most during relaxation at the beginning of the finishingprocess, but often they compact even further in the course of the subsequentfinishing steps. Because of this the finished product has the precalculated andrequired width, weight of the fabric and extensibility.

Given these facts, area stabilization by means of hot air setting is usually notnecessary, which is a great advantage with regard to maintaining the fabricproperties. Since raschel fabrics are prone to creasing they are preferably treatedopen-width.

Relaxation of foundation garment fabrics is performed mostly on steaming tablesor in modified steaming systems, rarely in open-width washers or dry cleaningmachines. To ensure that the final products are free from creases, they should beprocessed roll to roll rather than plaited.

Sometimes hot air setting is performed, e.g. to improve the elastane runback.The fabric is set at 180-195°C for a period of approximately 20–40 seconds.Exposure time and temperature should always be kept to a minimum.

Most types of raschel fabrics are dyed open-width on beam dyeing machines.Some qualities, however, (e.g. jacquard nets) may be dyed in rope form on winchbecks or, to reduce the risk of creasing, on overflow or jet dyeing machines.

Intermediate drying can easily and economically be carried out in a jet ribbondrier; here, the foundation garment fabric is treated completely tensionless andcan thus shrink freely, which is essential with regard to the stretch of the finalproduct. Drying is effected at temperatures ranging from 80 to 130°C.

Nowadays, however, intermediate drying of foundation garment fabrics isnormally carried out in the tenter at temperatures between 120 and max. 160°C.The tentering width should be a few centimeters less than the required width ofthe final product and – unless the desired running length and m2-weights do notallow for it – the overfeed should be sufficient to enable optimal shrinking withoutdisturbing the smooth and trouble-free running of the fabric.


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Raschel power nets are nearly always provided with a chemical finish to achievethe required hand and necessary dimensional stability. The finish is applied ina padder with good, uniform squeezing effect. Then the fabric is dried, andpossibly cured, by feeding it continuously through the tenter.

Today, mainly finishes containing little or no formaldehyde are used. Additionalfillers or softening agents are only applied, if the customer’s specifications renderthem necessary, because the excessive use of softening agents may cause theDorlastan threads to show an unfavorable tendency to creep back at the seamsin the ready-to-wear apparel.

Final drying of the finished foundation garment fabric is performed in the tenter at temperatures between 130 and 160°C. With non-crosslinking finishing agentsthe actual temperature and contact time is determined exclusively by the dryingeffect; in case of crosslinking dressing agents it is the curing conditions to beobserved that determine these variables. Make sure to adjust the correctoverfeed for these goods that tend to stretch lengthwise, so that the defined weight of the fabric, running length and extensibility are achieved.

It is quite common practice to enhance the whiteness of white foundationgarment fabrics by adding suitable tints to the finish bath.

To improve the touch and the surface smoothness of the fabric, decatizing issometimes employed as aftertreatment.

In such cases it is recommendable to work at temperatures between 120 and130°C and to expose the fabric to the steam for another 2 minutes after it hasevaporated from the cloth before the articles are cooled down thoroughly bymeans of suction (for about 5 minutes).

2.2 Warp-knits

Knitted fabrics produced on warp-knitting machines with intermeshed Dorlastanfilament yarns as looped threads are far less stable than raschel fabrics and aremore likely to curl at the edges.

Elastic warp-knits have a very pronounced shrinking tendency, which is muchlarger than that of raschel power nets. So if warp-knits were allowed to shrinkfreely, they would often shrink much more than is accepted by the customer;width and length would be insufficient, extensibility too large and thus weight ofthe fabric too big. Given the above mentioned additional strong curling tendency,hot air setting is a must in the finishing process of such qualities in order to avoidedge curling and to achieve the required final product data. So the finishing of warp-knits differs considerably from that of raschel power nets.

On the other hand, warp-knits are less prone to creasing, so that they can safelybe rope-dyed, if the necessary precautions have been taken.


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The pronounced shrinking tendency of elastic warp-knits makes a controlledshrinkage absolutely necessary. A very good relaxation effect is reached bysteaming the greige fabric on steaming tables. Given the strong tendency to curlat the edges, warp-knits should be pinned down at the edges and be fed to themachine with a defined overfeed. This prevents curling and excessive shrinkage.

Tenter frames with steaming equipment at the tenter feed end provide a veryeconomic solution to combine shrinkage and hot air setting. This method is oftenused, but it has the disadvantage that the lubricants of the unscoured fabricevaporate and may then precipitate on the tenter or on the fabric.

Relaxation of the greige fabric can easily be combined with thorough cleaning ofthe greige fabric in an open-width washer working at low tension. It has provenuseful to insert a scray as an intermediate cloth store between open-widthwasher and subsequent tenter. This reduces fabric tension because the warptension is particularly low compared to the common method of immediatelyfeeding the fabric to the tenter by means of saddle rolls.

The insertion of a scray before the tenter permits continuous operation even if large numbers of rolls are combined to form batches, and if the ends of theindividual pieces must be sewn together without interrupting the work flow. Toavoid lay marks and creases, elastic warp-knits must always be conveyed fromroll to roll from the time they arrive as greige goods up to hot air setting, andmust never be plaited down in between.

Warp-knits may be dyed in rope form on winch back, overflow or jet dyeingmachines or open-width on beam dyeing machines. Even though warp-knits are not very susceptible to creasing, you should make sure that the liquor-fabricratio is not too small if you dye in rope form, that temperatures are changed slowly and dyebath lubricants (e.g. 0.5–2.0 g/l PERSOFTAL®L or 0.1–0.5 g/lPERSOFTAL®LU) are added to prevent creasing. It is not really necessary to sewthe dyed fabric into a tube, but it becomes increasingly recommended the morepronounced the fabric’s tendency to curl at the edges (especially lock-knits) andthe less intensive the prior heat setting was.

Overflow or jet dyeing offer all the advantages of rope dyeing such as fullvolume, pleasant touch, strong density with the corresponding high extensibility,no risk of moiré, and in addition to that a much lower risk of running creasescompared to winch beck dyeing.

For quality reasons, dyeing times and temperatures should be restricted as muchas possible, i.e. the maximum working temperature is 98–100°C (except forpolyester/Dorlastan blends that are dyed at 120–130°C).

The most appropriate softening agents for warp-knits are those creating a soft,supple touch and a pleasant, smooth surface. Note that all softening agents witha smoothing effect also reduce the inner frictional forces in a fabric and thusincrease extensibility at constant elongation force and improve elastic recovery.


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The commonly applied softening agents, such as PERSOFTAL®SWA01,PERSOFTAL ASN 01, PERSOFTAL U or PERSOFTAL OE, are well suited to meet the standard expectations with regard to fabric handle. They can be addedeither by the exhaust method or in the padder. Silicone rubber or silicone water-repellent products are the right softening agents to meet particularly strictrequirements with regard to smoothness and suppleness of the final fabric.Excessive smoothness, however, impairs safety in the manufacture of ready-to-wear apparels.

For final drying, the tenter frame is used. The drying temperatures range from120 to 160°C. Overfeed and width of the frame must be adjusted accordingly toachieve the required length and width that have already been defined for heatsetting.

Sometimes a fabric is extended to much during dyeing due to excessivelengthwise tension. Unfortunately it is nearly impossible to repair this undesirableeffect by a corresponding overfeed in final drying, because the fabric hassuffered re-fixation during the dyeing under tension at the boil.

If, however, a fabric has shrunken in width or length during dyeing at low tensionbecause the previous heat setting was insufficient, it is possible to compensatefor this effect and to reach the required final product dimensions in the finaldrying process. But the finished product may still shrink later during storage,transport or scouring. Such undesirable subsequent shrinkage can be avoidedby drying the fabric at 120–160°C as described above, and then subjecting it toa second heat setting in the defined final state. However, slight changes of shademay result from this procedure.

2.3 Knits

Knits are produced by two different methods, flat knitting and circular knitting.

The finishing properties of knits are similar to those of warp knits. However, knits reacteven less sensitive to finishing processes and are less prone to creasing than warpknits because of the predominant use of spun yarns.

2.3.1 Flat Knits

Flat knits containing Dorlastan are usually dyed in the yarn, so that no piecedyeing is required. For waistbands and tops and fully fashioned knitwear, thefinishing is restricted to steaming; yard goods require additional setting.

2.3.2 Circular Knits

Circular knits must be delivered either in tubular form or open-width. The greigegoods must be divided into these two groups according to article characteristicsand the intended field of application.


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Fabrics that are processed and delivered in tubular form, e.g. elastic waistbandsfor underwear, are treated on becks, in jets, or in continuous machines.Relaxation takes place during the entire wet treatment. Subsequently, the goods are hydroextracted, dried in jet ribbon driers without setting, and thencalandered. Since the product is not subjected to any setting, the required shrinkresistance must be reached by shrinking the product sufficiently (by maximumoverfeed in longitudinal direction, no stretching to the limit in vertical direction)during other finishing procedures.

Recently, thermosetting of tubular knitted fabric on tube setting plants has beenintroduced into finishing; the tube can either be treated by the vertical or by thehorizontal method.

By this setting technology the article properties like m2-weight, extensibility, tubewidth and running length can be varied within certain limits like with open-widthtreatment.

However, it must be taken into consideration that excessive vertical stretchingmay leave lateral marks (depending on the fiber).

Circular knits that must be delivered open-width and be subjected to heat settingin order to create dimensional stability and to reduce the tendency to curl at theedges can be dyed in rope form or open-width. Which technique is chosendepends primarily on the fabric properties but also on the equipment availibility.Articles that are not prone to creasing can be rope-dyed without any risk of crea-se formation; additional advantages of this method are a large fabric volume anda soft touch. Knits that are prone to creasing should be dyed open-width on thebeam to ensure a smooth finished product without creases.

Any open-width dyeing must be preceded by a reliable heat setting. Otherwisethe knitted fabric will shrink in width, which results in color irregularities becausepart of the beam perforation becomes uncovered. In addition, moiré effects willoccur. With beam dyeing, smooth, elegant, but also less voluminous finalqualities are achieved.

Knits should always be pre-scoured because they may contain lubricated fiberstaple yarns or be produced from raw cotton. Both types of fibers may containimpurities, which should be removed prior to any heat setting. If the fabric is firstset and scoured afterwards, it will be much more difficult to wash out anycontaminations. Pre-scouring of non-set knitted fabrics must be performed verycarefully because of the large risk of crease formation (liquor ratio, temperaturecontrol, moving the fabric during the process, possibly open-width treatment).


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2.4 Wovens

In contrast to knits, for which mainly bare Dorlastan is used, wovens are producedexclusively with Dorlastan combination yarns. In combination yarns, the Dorlastanthread is normally well covered.

There are two types of fabrics, mono- and bi-elastic ones. In mono-elastic fabrics,the Dorlastan is worked in either in warp or in weft direction. Bi-elastic fabricshave incorporated Dorlastan threads in both directions.

Experience has shown that elastic fabrics with a large percentage of elastic yarns(in most cases knits made of smooth textile filament yarns) shrink more than isrequired to achieve the desired stress-strain properties. So the shrinkage must becontrolled and limited. Elastic wovens, however, often contain only a very lowpercentage of Dorlastan, which is frequently combined with staple fiber yarns.This combination causes a high inner friction going along with a rather sluggishshrinkage. If the standard finishing methods for elastic wovens fail to producesufficient compression to reach the defined stress-strain values, additionalmeasures must be applied. A very effective technique to achieve a clearlyimproved shrinkage that normally meets standard requirements is a tension-freetreatment with hot air (e.g. in the tenter providing for the possibility of shrinking) or dyeing at the boil (e.g. for piece dyeing in rope form).

With wovens, it would be possible to create a greige fabric with optimalshrinkage, exactly the expected fabric weight and the desired degree ofrecoverable stretch and – being a non-shrinking fabric – also with good shrinkingvalues, without applying any setting. The actual situation, however, is different.The conditions in greige good production as well as in finishing always vary from one batch to the next. Moreover, the buyer of the finished product may orderqualities of different m2-weights or stretch values. Such variations can only bereached during finishing, which makes hot air setting necessary in nearly allcases, because it is hardly possible to obtain all required characteristics in thefinished fabric by any other method.

After hot air setting further finishing processes may be required to obtain thedefined quality level. Such finishing may lead to an elongation of the elasticfabric, even if it is treated at low tension. If such an effect occurs, it must bereversed later by shrinking, so that the fabric properties obtained by the settingare regained. Possible methods are, for example, tension-free steaming orsanforizing.


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3. Bleaching, Fluorescent Whitening and Dyeing

These important processes should be performed very carefully, because they donot only give the fabric its final color, but also have a decisive influence on thequality of elastic fabrics.

For piece dyeing which does not require staining of the Dorlastan fiber, dyestuffsexclusively determined for the non-elastic fibers are used.

Below you find some information about the various blends that are available.

3.1 Dorlastan/Polyamide

From the point of dyeing, polyamide filament yarns or fibers are ideal partners forDorlastan, because both fiber types can be dyed with the same categories ofdyestuffs, and the quality of the elastane is not impaired under the normal dyeingconditions.

3.1.1 Scouring

As already explained in item 1.3.1, pre-scouring is recommended to achieveoptimal final colors.

• Continuous scouring • Discontinuous scouring

Impregnation in the 1st compartmentof the washing machine – 3 ml/l Diadevin® DSP– 3 ml/l Diadevin® DSP – pH 8–9– pH 8–9 – Exposure time: 30 min.– Temperature: 80°C – Temperature: 80°C

Rinsing in the 2nd and 3rd compartment Rinse twice: 15 min. at 70°Cat 70–80°C (counterflow), Rinse twice: cold with overflow4th compartment cold (counterflow)

3.1.2 Fluorescent Whitening

Today, scouring, fluorescent whitening and reduction bleaching are preferablycombined, whereby a fluorescent whitening agent shows mostly affinity to thepolyamide. Optimal color light fastness is best achieved with BLANKOPHOR®

CLE products.

The one-bath method and the following recipe is applied:

– 0.5–1.0 ml/l Diadevin® NSE or Diadevin® UN (APEO-free)– 2.0–3.0 g/l Blankit® CP– 2.0–2.5 BLANKOPHOR® CLE as liquid (or CLE liquid B)– pH 5 (acetic)


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3.1.3 Dyeing

The following classes of dyestuffs can be used for pure polyamide as well as forpolyamide/Dorlastan blends.

– Acid dyestuffs for light and medium shades– Metallic complex dyestuffs for medium and dark shades or afterchroming

dyestuffs for very dark shades, particularly black– In special cases disperse dyestuffs may be used for very light shades.

Although polyamides and elastanes can be dyed with the same types ofdyestuffs, they react differently to the various classes. This must be taken intoconsideration when selecting the dyestuff.

Whereas disperse dyestuffs are absorbed by polyamides and elastanes withmore or less the same intensity, so that no larger differences in shade occur, acid dyestuffs create darker shades with polyamides than with elastanes. Thedifference in shade varies, however, from dyestuff to dyestuff.

In addition to that, the dyeing properties within the group of polyamides differconsiderably from fiber to fiber, and in particular between polyamide 6 andpolyamide 6.6. In extreme cases, the combined effect of the above mentioneddifferences in dyeing behavior may result in hardly stained elastanes that grinthrough, if certain acid dyestuffs (with better affinity to polyamides) or metalliccomplex dyestuffs are used.

The grin-through effect does not occur with clear Dorlastan (types V 500, V 800),because the clear Dorlastan thread is transparent. Nevertheless, the percentageof Dorlastan and the geometric appearance of Dorlastan in the article must stillbe taken into consideration when choosing the dyestuff.

When using acid dyestuffs, it must be taken into account that dull and clearDorlastan appear differently in Dorlastan/polyamide blends. The right choice of dyestuff and auxiliary agent is important, especially in case of high elastanecontent (more than 30%).

Articles made of polyamide and dull Dorlastan can be dyed with acid or metalliccomplex dyestuffs that are exclusively tailored to the polyamide component withregard to affinity and fastness, if the elastane share does not exceed 20%. Incase of darker shades, however, the aftertreatment must include the stainedDorlastan and be appropriate to stabilize its shade.

To avoid grin-through in articles made of polyamide and matted Dorlastan,special measures are required. They must either be dyed with selected dyestuffsthat produce satisfactory tone-on-tone dyeing with standard leveling agents, or,in special cases, with the help of suitable auxiliary agents like ASTRAGAL® PAN,which enhance the solid dyeing. The use of such agents, however, will entail aslight unavoidable deterioration of the wet and crock fastness. With unfavorabledyeing conditions (unfavorable liquor circulation, little liquor exchange) it is


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essential to choose the best possible combination of dyestuffs and to use nocationic auxiliary dyeing agents.

• Standard combinations of auxiliary dyeing agents

– 0.5–1.0% AVOLAN® IS– 0.2–1.0% LEVEGAL® FTS K 01 or 0.4–2.0% LEVEGAL® LPA – ph 8–4

• Recipe for better staining of Dorlastan

– 2% AVOLAN® IW heat up from 40°C to 98°C– ph 7.5–5.5 within 45 minutes, keep– x% TELON®, SUPRANOL®, ISOLAN® dyestuff at 98°C for 30 minutes– 0.5–2.0% ASTRAGAL® PAN (and keep at 98°C for 30 minutes)

(With some dyestuffs, this combination of auxiliary dyeing agents should not beused; see dyestuff table in the appendix.)

The Dystar product range of acid and metallic complex dyestuffs has beentested with the two aforementioned combinations of auxiliary agents and hasbeen optimized to produce proper tone-on-tone dyeing of blends containingpolyamide and Dorlastan. The attached dyestuff table will help the dyer to selectthe best dyestuff.

3.2 Dorlastan/Polyester

A Dorlastan/polyester combination is a difficult blend for the finisher, becausepolyester types with normal dyeing properties must be dyed at highertemperatures than polyamide (HT conditions: 120–130°C) or require the use ofcarriers. This may lead to a deterioration of the elastic properties of the finalarticle, although Dorlastan still surpasses all competitive elastanes.

Since the disperse dyestuffs used for this blend also stain the elastanecomponent considerably, an alkaline reductive aftertreatment is required toobtain good wet fastness.

If the polyester type in the blend allows the use of cationic dyestuffs, theDorlastan is hardly stained, provided the correct dyestuff is chosen.


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3.2.1 Scouring

The following scouring procedure has proven to be a good choice:

– 2.0–4.0 ml/l Diadevin® DSP– possibly 1.0 ml/l RESPUMIT® NF– possibly 1.5–2.0 ml/l PERSOFTAL® L or 0.2–0.5 ml/l PERSOFTAL® LU– pH 8–9

Exposure time: 20–30 minutesTemperature: 70–80°CLiquor ratio: 1:10Rinsing: 2 x at 80°C

1 x cold with overflow

3.2.2 Fluorescent Whitening

In addition to the exhaust method with carriers, there are some other methodsthat are particularly recommended for fluorescent whitening because of their costefficiency:

• Thermosol method

In this method, the brightening agent is padded in the foulard. Subsequently, thefabric is thermosoled in the tenter without intermediate drying. This step may becombined with hot air setting. The following recipe is suggested for greige goodtreatment:

– 1.0–5.0 g/l BLANKOPHOR® ER liquid 330% 01

For shading:– Dianix brilliant violet B– Dianix brilliant violet R

Liquor absorption: 60–80%Drying at: 140°CThermosoling: 20–30 s at 190–195°C

• AF method (adsorption/fixation method)

Here, the brightening agent is applied as an additive on the surface of the fabricby the exhaust method (a fabric pretreated that way acquires a yellow cast). Afterrinsing, the fabric is dried and heat–set in the tenter. During this stage, thefluorescent whitener is thermosoled into the fabric to produce the desired level ofwhiteness.


16

When applying the AF method, no anionic auxiliary agents must be used,i.e. previous anionic scouring is not allowed, because this would impair anundisturbed absorption of the whitener by the fabric.

• Adsorption phase

– 0.1–0.3% BLANKOPHOR® ER liquid 330% 01– 1–2% Glauber salt– Acetic acid ph 4.5

The treatment is always started cold. The degree to which the fluorescentwhitener is adsorbed is highly dependent on the dyeing conditions. With rope orjig dyeing, no adsorption will usually occur when the liquor is cold. For dye-bathexhaustion, a temperature of about 40–50°C is required. The temperature israised slowly, i.e. by about 1°C per minute. The adsorption phase is completedwith a cold rinse.

• Fixation phase

After drying at 140°C, the fabric is finally set at 190–195°C for 20 to 30 seconds.If no fiber setting is required, the whiteness may also be developed by drying at170–180°C.

3.2.3 Dyeing

To keep the damage to the elastic properties of a fabric made of a polyester/Dorlastan blend within acceptable limits, the dyeing temperature must beincreased carefully and suitable carriers must be selected in the appropriateamounts.

Two methods are available:

• Dyeing with carriers:Temperature increase and carrier (type, amount) must be adjusted to eachother to reach an acceptable compromise.The following procedure is applied:

– 1–2% LEVEGAL® DLP– x% carrier, e.g. LEVEGAL® PTN 01– y% disperse dyestuff– pH 4.5maximum dyeing temperature 108–115°C


17

• Dyeing without carriersIf carriers cannot be used for ecological reasons, dyeing can be performedunder HT conditions. The following procedure is applied.

– 1–2% LEVEGAL® DLP– y% disperse dyestuff– pH 4.5maximum dyeing temperature 125–130°Cmaximum exposure time 30–45 minutes

The range of disperse dyestuffs offered by DyStar with the respective applicationinformation is enclosed in the appendix.

Starting temperature, heat-up rate and carrier amount used in the dyeing processdepend on the dyeing rate of the polyester and on the type and the quantity ofthe applied disperse dyestuff. For further information, please refer to therecommendations of the dyestuff manufacturers. After dyeing, the fabric needsalkaline reductive aftertreatment in order to improve colorfastness. The followingrecipe is used:

– 2–4 ml/l caustic soda 50%– 2–4 g/l hydrosulphite20–30 minutes at 80°C(For lighter shades, 70°C and 3g/l soda ash instead of caustic soda suffice.)

3.3 Dorlastan/Wool

A Dorlastan/wool blend is not problematic with regard to dyeing, because thestandard conditions of wool piece dyeing (acid dyestuffs and temperatures below100°C) do not have a negative effect on the elastic properties of Dorlastan. Aciddyestuffs usually produce solid dyeing of both the wool and the Dorlastanthreads; no special dyestuffs or auxiliary agents are necessary. Moreover, theelastane share of such blends is usually rather small and hardly visible in thefinished fabric.


18

3.4 Dorlastan/Cotton

The standard medium for cotton dyeing and finishing is an alkaline medium.Blends containing Dorlastan, however, must not be exposed to the alkalineagents without control. The agents’ effect combines with those of heat and timeand might have a negative impact on the properties of the elastane.

The following dyeing and finishing procedures are recommended:

• Substantive dyeing

Can be applied without hesitation even with a fastness improving aftertreatment,if required.

• Reactive dyeing

With dyestuffs that are suited for a dyeing temperature of 50°C according to themanufacturer’s data.

• Indanthren dyeing

By the IK, IW, and IN method up to max. 60°C.

• Sulfur dyeing

By procedures with a reduced amount of alkali additives (e.g. sulfhydrate) atapprox. 70°C.

• Boiling off

Should be performed with the lowest possible amount of alkali additives(2g/l soda)

• Bleaching

• Caustic treatment and mercerizing

Can be applied without negative effects despite of the high amount of alkaliadditives because processing temperatures are low.


19

Add the usual stabilizers. In practice, the following recipe is applied successfully:

Winch back, liquor-fiber ratio1:30 soft water

– 0.2 g/l magnesium sulfate– 2.0–4.0 m/l DIADAVIN® DSP 01 (APEO free)– 0.3–0.5 ml/l BAYSTABIL® LF– 0.5–1.0 g/l BAYSOLEX® EXT-N– 6.0–10.0 ml/l hydrogen peroxide 35%– Caustic soda pH 10.5–11.0– 0.2–0.8% BLANKOPHOR® BA liquidfor 30–60 minutes at 90–95°C

Rinse thoroughly and apply the following aftertreatment to improve the whiteeffect:

– 2.0 g/l BLANKIT® IN– 3.0 g/l sodium sulfatefor 30 minutes at 70°C

Special surface finishes, e.g. by enzyme treatment („Biofinish“) are possible,since they are not detrimental to the Dorlastan.

Note

If you have any questions on dyeing or finishing matters, please do not hesitateto contact our Marketing Dorlastan department:

Dormagen, Germany Phone +49 21 33 / 51-50 85Bushy Park, USA Phone +1 84 38 20-65 10


20


21

Dyeing Procedure

(%) 1/1 V 500 V 850 V 900S.D.

Telon Yellow FG 0,5 2 1 2

Telon Yellow RLN micro 0,65 1 1r 1

Telon Yellow FRL micro 1,0 2 1 2

Telon Yellow 4R micro 0,65 2 1 2

Telon Brown 3G 3,4 2 1 1r

Telon Red FRL micro 1,2 3 2 3

Telon Red 2BL micro 0,7 3 2 3r

Telon Red 2B 0,8 3 2 3

Telon Red BRL micro 0,7 2 1 3

Telon Blue RR 0,7 3 2y 3

Telon Blue BRL micro 1,2 1 2 1

Telon Blue GGL 1,7 2 1 2y

Telon Yellow A3GL 0,7 3 2 3

Telon Yellow ARB 1,0 3 1 3

Telon Yellow A2R 0,9 2 1 3

Telon Yellow A3R 0,85 2 1 3

Telon Orange AGT 0,5 2 1 3

Telon Red A2FR 1,3 2 1 2

Telon Red AFG 0,65 3 2 3

Telon Rubine A5B 0,35 2 1 2

Telon Blue AR 2,6 2 1 2

Telon Blue AGLF 1,8 3 2 3

Telon Blue AFN 3,0 3 2 3

Telon Blue A3GL 2,5 3b 2 3

Telon Navy AMF 1,6 2 1 2r

Telon Black AMF 1,75 1br 1y 1r

Telon Flavine M-7G 0,75 2 1r 2

Telon Yellow M-5GL 1,7 1r 2 2

Telon Yellow M-4GL 1,0 2 2r 2

Telon Orange M-GSN 1,3 1 2 2

Telon Red M-R 0,6 1 1 1

Telon Red M-GWN 1,1 2 1 2

Telon Red M-BL 0,85 2 1 2

Telon Red M-3B 0,5 1 1 1r

Telon Rhodamine M-BN 0,3 3bl 2bl 3bl

Telon Violet M-RWN 1,4 1 2 3

Telon Blue M-BLW 2,7 2 3 3r

Dyeing of Polyamide / Elastan Blends:Staining on Dorlastan Type V 500, V 850 and V 900


22

Dyeing Procedure

(%) 1/1 V 500 V 850 V 900S.D.

Telon Blue M-RLW 2,7 2 3 3r

Telon Blue M-GLW 2,8 2 3 3

Telon Blue M-2R 1,8 1 2 2

Telon Turquoise M-GGL 2,1 2 3y 3

Telon Turquoise M-5G 2,3 1 3y 3

Telon Green M-BW 1,6 1 2 2bl

Telon Green M-6GW 2,0 1 1 2bl

Isolan Yellow K-GLN 250 % 1,0 2 2 2

Isolan Yellow GRL 0,9 2 1 1

Isolan Yellow K-PRL 200 % 1,3 1br 1r 1r

Isolan Orange K-RLS 150 % 2,0 2 2bl 2bl

Isolan Scarlet K-GLS 150 % 1,9 3 3 3

Isolan Bordeaux R 220 % 0,95 1 1bl 1bl

Isolan Brown K-3GLS 150% 2,1 1y 1r 1r

Isolan Blue 3GL 1,3 2 1 1

Isolan Grey K-PBL 200 % 1,3 2 1 1

Isolan Black 3RL 2,7 2 3 3

Isolan Yellow SP-2RL 1,8 2 2br 2

Isolan Red SP-G 1,2 2 1r 2r

Isolan Blue SP-R 1,1 2 1 2

Isolan Grey SP-G 1,1 2r 1 2

Isolan Orange S-RL 1,2 1br 1 2r

Isolan Red S-RL 1,0 1 1 2

Isolan Brown S-GLN 1,0 1 2 2

Isolan Brown S-RL 1,0 1 1r 2

Isolan Navy Blue S-RL 2,0 1r 2r 2

Isolan Olive S-G 1,0 1 2 2

Isolan Grey S-GL 1,8 1 3 3

Isolan Black 2-BGL 2,9 2r 3 3

Isolan Yellow 2S-GLN 0,92 2 1r 2

Isolan Yellow 2S-RL 0,85 2 2r 2

Isolan Scarlet 2S-L 1,3 1y 1 1

Isolan Red 2S-BR 1,2 2 2r 2

Isolan Bordeaux 2S-B 0,95 1y 1 2

Isolan Brown 2S-BL 0,85 1y 1r 1



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Blends: PA / Dorlastan 80/20PA: PA 6.6Elastan: Dorlastan V 500, V 850, V 900

Evaluation:1 = slight dyeing of Dorlastan fibre y = yellowish2 = medium dyeing of Dorlastan fibre r = reddish3 = ton-in-ton-dyeing br = brownish

bl = bluish

dyeing procedure:0,5 % Levegal FTSK 010,5 % Avolan IS only M.C. dyespH depending on the dye range98° C / 45 min.


Dyeing Procedure

(%) 1/1 V 500 V 850 V 900S.D.

Isolan Dark Blue 2S-GL 2,4 1br 2 2

Isolan Olive 2S-BGL 1,0 1y 1r 1r

Isolan Black 2S-LD 2,5 2r 3 3r

Isolan Black 2S-LGN Liq. 6,25 1y 2 2y

Appendix

1. Dyestuff recommendations for dyeing PES/Dorlastan® blends

The even exhaustion and diffusion properties of composite dyestuffs are keyfactors for a successful dyeing of PES/Dorlastan blends. Due to these properties the exposure time is shorter and reproducibility is optimized – „Right-First-Time“ –. The optimized reproducibility helps to avoid a subsequent additionof dyestuffs with its negative effect on the characteristics of Dorlastan.

1.1 Dyeing at 125–130°C

„Right-First-Time“ dyeing of PES/Dorlastan blends with good reproducibility andoptimal wet fastness can be achieved with the selection of dyestuffs listedbelow.

1.1.1 Dianix® AC-E dyestuffs for light shades


24

-70 -50 -30 -10 10 30 50 700

0

-50

-30

-10

10

30

50

70

90

b

a

Yellow AC-E new

Red AC-E 01

Blue AC-E

110


25

Three-color combinations:• Medium shades: Dianix yellowish brown CC/ruby CC/blue CC.• Dark shades: Dianix yellowish brown CC/ruby CC/navy CC.• In bluish red shades (cherry red, wine red), washfastness can be increased

by the use of Dianix red K-2B.

-70 -50 -30 -10 10 30 50 700

0

-50

-30

-10

10

30

50

70

90

110

b

a

yellow SE-G

brilliant blue R

yellowish brown CC

red K-2B

violet CCturquoise S-BG

green CC

black CC-G

navy CC

blue CC

red CC

red C-4G 150%

ruby CC

1.1.2 Selected medium energy range Dianix® dyestuffs for medium todark shades


26

Three-color combinations:• Dianix yellowish brown XF/ruby XFN/navy XF• Dianix flavin XF/scarlet SF/bleu XF – for ultimate washfastness.

1.1.4 Advantages

• Tone-on-tone staining creates optimal reproducibility and minimizes shadecorrections.

• Good general fastnesses with Dianix AC-E dyestuffs and selected mediumenergy range Dianix dyestuffs.

• Three-color combinations including „tone-on-tone“ staining of the elastanefiber after reduction cleaning minimize „grin through“ and shade changesduring post-setting.

• Very good washfastness with selected Dianix XF/SF dyestuffs.

-70 -50 -30 -10 10 30 50 700

0

-50

-30

-10

10

30

50

70

90

110

b

a

flavin XF

yellowish brown XF

blue XF

navy XF

black XFruby XFN

carmine SF

scarlet XF

1.1.3 Selected Dianix® XF/SF dyestuffs for dark shades of ultimatewashfastness


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1.2 Dyeing at 115°C

1.2.1 Dianix® AC-E dyestuffs for light shades

1.2.1.1 Advantages


• Good general fastnesses.• Largest possible dyestuff standardization creates optimal reproducibility.• Good level dyeing properties and covering of differences in material.• Extraordinary light fastnesses.

-70 -50 -30 -10 10 30 50 700

0

-50

-30

-10

10

30

50

70

90

110

b

a

yellow AC-E new

red AC-E 01

blue AC-E

1.2.2 Selected medium energy range Dianix® dyestuffs for medium todark shades


28

Three-color combinations:• Medium shades: Dianix yellowish brown CC/ruby CC/blue CC.• Dark shades: Dianix yellowish brown CC/ruby CC/navy CC.• In bluish red shades (cherry red, wine red), washfastness can be increased by

the use of Dianix red K-2B.

1.2.2.1 Advantages


• Good general fastnesses.• Three-color combinations including „tone-on-tone“ staining of the elastane

fiber after reduction cleaning minimize „grin through“ and shade changesduring post-setting.

The Dianix XF/SF dyestuffs are not always recommendable for dyeing at 115°Cbecause color build-up and fastness levels are considerably reduced at thisdyeing temperature.

-70 -50 -30 -10 10 30 50 700

0

-50

-30

-10

10

30

50

70

90

110

b

a

yellow SE-G

brilliant blue R

yellowish brown CC

red K-2B

violet CCturquoise S-BG

green CC

black CC-G

navy CC

blue CC

red CC

red C-4G 150%

ruby CC

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