Customer Information: A Guide To Pretreatment, Dyeing and Finishing

Ciba Specialty Chemicals Inc.
Colors
Value beyond chemistry
Customer Information
Nov. 1999 / 1X4009.E
Lyocell
A guide to pretreatment, dyeing and finishing
This guide briefly summarizes Ciba’s total present-day selection of recommendations for
the wet processing of fabrics either knitted or woven from fibres known collectively by the
generic name “Lyocell”. It covers both the products and the methods currently
recommended and is intended to provide the dyer and finisher in particular with the help
he so urgently needs to find the application routines and products which will ensure
compliance with the various end-product requirements, taking into account this fibre’s
special properties.
Wide-ranging application development work has revealed the extent to which specific
multifunctional reactive dyes cause interfibrillar crosslinking. It has also now resulted in a
dyeing technique with a beneficial impact on the characteristic fibrillation tendency of
textiles made from Lyocell fibres.
Though by now practicable recommendations have been worked out for the various
processing steps, a whole range of matters are still outstanding. The joint search for
solutions to these through constructive communication means challenging opportunities
for all involved within the chain of cooperation.
The present guide is therefore not intended as an inalterable compilation. On the contrary
it will be constantly updated in active collaboration with the fibre producer, machinery
builder, dyes and auxiliaries manufacturer and, last but not least, the dyeing and finishing
specialist to include new knowledge and findings in this difficult but interesting field.
Page 1, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

Lyocell
Contents
page
1. Lyocell fibres - definition / market position 3
2. The NMMO process 4
3. Lyocell fibre properties 6
4. Fibrillation / definition / influencing factors / assessment 7
5. Pretreatment 8
6. Primary fibrillation / enzymatic defibrillation 8
7.1 Dyeing with CIBACRON LS dyes (method, dye selection) 9
7.2 Dyeing with CIBACRON FN dyes (method, dye selection) 11
8. Dyeing with Ciba SOLOPHENYL dyes (method, dye selection) 15
9. Pad-batch dyeing with CIBACRON C 18
10. Printing 19
11. Peachskin effect / resination 19
12. Reducing fibrillation 19
13. Machinery requirements for dyeing and finishing Lyocell items 22
14. Selection of auxiliaries 23
15. Potential process route 26
16. Bulk trial with Lyocell / CIBACRON LS 28

Lyocell
1. Lyocell fibres - definition / market position

The Lyocell fibre represents one of the greatest innovations in the fibre industry as a whole since the
development of synthetic fibres. Lyocell is a new cellulosic fibre which is produced by a new process and
exhibits a unique combination of physical properties.
These fibres translate through into fabrics which show high strength and excellent stability.
The exploitation of these properties in fabric finishing has allowed a wide variety of truly unique
aesthetics to be created for high fashion apparel.
The term Lyocell is the generic name for this new cellulosic fibre generation established in 1989
(according to BISFA - International Bureau for the Standardization of Man - Made fibres).
At present well-known Lyocell fibres produced by the NMMO process are:

Trademark Manufacturer Staple fibre Filament Bright Dull Notes
Tencel  ACORDIS UK / USA X X first manufacturer
Lyocell Lenzing Lyocell GmbH, Austria X X pilot plant, bulk plant in 1997
by Lenzing 
NewCell  ACORDIS, Germany X X X initial patent holder, licensed
to Lenzing and Courtaulds
Alceru  Thuringian Textile and Plastics X X pilot plant
Research Institute (TITK),
Germany
Cocel  Hanil Synthetic Fiber / Korea X pilot plant, bulk plant in 2002
In Grimsby Courtaulds now operates a pilot Lyocell fibre plant (capacity 2,000 t/year) for product
development focused on clothing and mainly on technical applications (Courtaulds Lyocell). Since
September 1997 the production plant in Grimsby is on stream (capacity 42,000 t/year; worldwide
100,000 t/year). By the year 2005 ACORDIS expects a Lyocell capacity of 150,000 t/year.
Since mid - 1997 the Lenzing AG Lyocell plant - initial capacity 15,000 t/year, increased to 35,000 t/year
(currently postponed !) - is operational.
The latest manufacturer of Lyocell Hanil Synthetic Fiber (Korea) plans to start with the full-scale
production of their “Cocel” in the second half of 2002. Two 30-tons/day lines are to be installed, and
two more lines will be added by 2004.
The market segments currently being studied are:

♦ denim
♦ ladies’ / men’s outerwear
♦ sports / leisure wear
♦ lingerie
♦ technical end uses (flame retardant )
♦ barrier cloths and abrasive belts
♦ hosiery

Lyocell
2. The NMMO process
(N - methyl morpholine N - oxide)
Besides NMMO, there are a number of other solvents which can likewise be seen and
assessed as alternatives to those used in the viscose process but which do not have
the same significance.
To develop the man-made cellulosic fibre industry in the long term, manufacturers
have begun to look at new routes of fibre production (CS2-free process) giving
improved fibre properties and performance characteristics.
Solvent systems worth considering for processing cellulose must meet the following
requirements:
♦ high cellulose dissolving power suitable for the preparation of a solution

with a sufficiently high cellulose concentration and good filterability
♦ easy recovery of solvent components
♦ promotion of useful fibre properties
♦ low environmental pollution
One such route involves the use of a solvent to dissolve cellulose directly.
For the Lyocell fibre a spinning process has been developed which is based on the
use of an amine oxide, N-methyl morpholine N-oxide, to dissolve the cellulose.
NMMO is an organic cyclic tertiary amine which appears to be one of the most
potent organic solvents for cellulose (C5 H11 NO2, M=117,1).

Lyocell
Principle
The cellulose is soaked in a mixture of NMMO and water. The pulp which is used as
the raw material is characterized by a medium degree of polymerization and DP
distribution.
Unlike in the viscose process, the cellulose is unsubstituted in the cellulose - amine
oxide solution.
This method is of a purely physical nature, i.e. there is no chemical reaction stage. It
comprises the physical processes of dissolving, deforming, coagulating and drying.
These fibres complete the range of products manufactured according to the
xanthate (chemical) process and will open up totally new fields of application.
NMMO is non-toxic and therefore very attractive as the basis of a manufacturing
process.
Thus the process utilizes materials which are environmentally clean. Solvent recycling
is an integral part of the process.
Waste products are therefore minimal, non-hazardous, and very easily controlled.
XANTHOGENATE - PROCESS NMMO - Process
NaOH è
Alkalizing Dissolve
Water è Make up NMMO
- NMMO Water
Maturing
S2 è Sulphidize
NaOH è NMMO
Water è
Dissolve Recovery
Maturing CS2
Recovery
Water
Filter / Degas Filter
Spinning bath Spinning bath

Spin Spin
(Sulphuric acid/Zinc) braking
Water, NMMO Destillate,
Water
Wash
Acid Water Effluent
Water è
Desulphurization COD, Zinc
Na2SO4
Bleach, Finish Bleach, finish Effluent
COD
Dry Calcination Dry

ê Na2SO4

Lyocell
3. Lyocell fibre properties

Lyocell fibres are characterized by a higher ratio of crystallite length to long spacing and by
a higher degree of crystallinity than modal and viscose fibres.
With respect to the elementary fibrils of Lyocell, this means that very short sections of low
order link together long sections of highly ordered cellulose molecules.
Crystallinity in the longitudinal direction of the fibre increases to the detriment of the
amorphous areas which are, therefore, better oriented. On the one hand this results in a
better order but on the other there is less scope for lateral connections to other
amorphous areas.
The formation of voids and also, most probably, their orientation are associated with this.
Lyocell fibres have a low rate of cluster formation. The amorphous areas are short and
oriented.
Crystallinity Crystallinity Orientation Cluster Cluster Cluster Crystallite
% in fibre direction factor fraction diameter length length
% fcr % fam% (nm) (nm) (nm)
Lyocell 59 90 67 73 0.28 36.5 289 21.3
Modal 38 55 52 42 0.87 39.4 184 16.1
Viscose 33 60 - 70 36 - 0.83 49 150 16.1
Polynosic 48 - 54 - 0.76 35.9 188 -
Unlike cotton, all regenerated cellulosic fibres lose part of their tensile strength in water,
i.e. in the swollen state. With Lyocell, however, this loss is significantly lower than in the
case of modal, polynosic and viscose fibres.
The special tensile properties of Lyocell fibres can be explained by the high orientation of
the crystallites as well as of the less ordered interlayers between the crystallites in the
elementary fibrils. This peculiar feature prevents distortion of the fibrils by the penetration
of swelling agents and thus promotes high wet tensile strength or modulus.
An increase in orientation improves the advantageous wet tensile properties, but at the
same time intensifies the unfavourable property of fibrillation by the same mode of action.
Wet tensile strength maximization is hence out of the question and a balance has to be
found.
TencelLenzing NewCell Alceru Modal Viscose Cotton PES Polynosic
Lyocell
Count (dtex) 1.4-1.7 1.3-1.7 1.1-2.2 1.5 1.7 1.7 1.7 1.7 1.7
Dry tenacity (cN/tex) 41 >35 34-40 47 34 25 28 56 38
Dry extension (%) 13 >14 6-12 14 14 17 10 25 11
Wet tenacity (cN/tex) 34 >28 22-27 40 20 14 32 54 26
Wet extension (%) 16 >17 8-14 16 15 21 11 25 12
Wet modulus at 5%ext(cN/tex) 270 > 160 260 110 50 100 210 120-180
Moisture absorption (%) 11.5 13 11-13 12.5 13 8 0.5 10-14
Water retention capacity(%) 65 65 75 90 50 3 60-70
Shrinkage low low low low medium high medium low medium

Lyocell
4. Fibrillation
Definition
Fibrillation is one of the most important physical properties of the Lyocell fibre.
Controlling and manipulating it during dyeing and finishing is the key to a wide
range of fabric aesthetics. It is caused by wet abrasion and occurs during wet rope
processing and domestic laundering. Fibrillation does not occur in open width
processing.
Fibrillation is a phenomenon characterized by fibrils peeling off along the
surface of individual fibres swollen with water when these are subjected to
mechanical stress.
The electron photomicrograph reveals the presence of both microfibrils and
macrofibrils.
Influencing factors
Owing to the high swelling capacity of Lyocell in water, mechanical stress causes the
fibrils to break and protrude from the fibre surface.
The high degree of fibrillation of Lyocell provides a basis for very interesting new
fabric aesthetics and a soft handle, such as the so-called peachskin effect (silk-like
appearance).
Apart from this kind of regular fibrillation, which is desirable, crease marks may form
and fabric greying result when dyeing in rope form and laundering. The following
preparation, dyeing and finishing recommendations can be followed to reduce
fibrillation if desired.

Lyocell
Assessment
Given that the Lyocell fibre tends to fibrillate in an aqueous medium and under the
action of mechanical stress, it seemed logical to imitate these conditions by wet
abrasion (Martindale test).
This method of assessment was used at first by the TITK / Rudolstadt (Germany) and,
following extensive developing and testing, is being used in our company to assess
dyed samples.
The test indicates that high wet abrasion strength means a reduced tendency to
fibrillation in practical use. It is known from resin finishing (cf. item 11. Resination)
that crosslinking reactions enhance wet abrasion strength, but also reduce dry
abrasion strength.
Optimization of these two parameters involves allowance for greying, a factor with a
crucial influence on performance in use.
The reflectance curves of the surfaces over the visible spectral region (400 - 700 nm)
are used to ascertain greying (after wash tests on fabrics dyed in rope form or semi-
continuously).
For this purpose the treated samples are compared with the original (untreated)
material, and greying is determined colorimetrically or visually.
5. Pretreatment
⇒ for specific recommendations, please contact Consumer Care
Division Pfersee / Langweid - Germany
6. Primary fibrillation / enzymatic defibrillation


Lyocell
7.1 Dyeing with CIBACRON LS dyes

The CIBACRON LS range
Yellow LS-4G Combination dye for brilliant shades / No photochromism
Yellow LS-R For combination shades
Orange LS-BR For combination shades with high light fastness / Especially for pale shades / No photochromism
Scarlet LS-2G For combination shades / Basis for red and scarlet shades / Light fastness limited
Red LS-6G Tinctorially strong red dye / Light fastness slightly better than that of Scarlet LS-2G
Red LS-B For combination shades
Brill. Blue LS- For brilliant blue shades / For green combinations with Yellow LS-4G / For purple comb. with Red
LS-B
G
Blue LS-3R For combination shades and high light fastness
Green LS-3B Cost-effective basis for forest green and khaki shades / Basis for deep combination shades
Navy LS-G For cost-effective combination shades / Basis for navy shades
Black LS-N Tinctorially strong, deep black dye
Migration method
°C
100
90
80
70
60
50
40
30
20
0 10 20 30 40 50 60 70 80 90 100 110 120130 140 150160 min.
A C B D E
Salt and alkali recommendations / soda ash:
C CIBACRON LS % up 0.5 0.5 - 1.0 1.0 - 1.5 1.5 - 2.0 2.0 - 2.5 above 2.5
A auxiliaries see page 23 - 25
B salt g/l 10 10 - 15 15 - 17.5 17.5 - 20 20 - 25 30
D soda ash g/l 3 3 3 - 3.5 3.5 - 4 4 - 4.5 5
E soda ash g/l 7 7 7 - 7.5 7.5 - 8 8-9 10
Salt and alkali recommendations / soda ash + sodium bicarbonate:
B salt g/l 10 10 - 15 15 - 17.5 17.5 - 20 20 - 25 30
D sodium bicarbonate g/l 2 2 2 2 2 2
E soda ash g/l 10 10 10 - 11 11 - 12 12 - 13.5 15
Reduced fibrillation tendency
due to crosslinking behaviour of the bireactive dyes, resulting in improved fabric appearance and
reproducibility of the desired effects

Lyocell
Washing off and aftertreatment

Procedures Notes
Rinse for 10 min at 50°C Rinse once if liquor ratio is 10:1 or above. Rinse twice if liquor ratio is
below 10:1 or intermittent / overflow rinse with 10 l water / kg fabric.
Rinse for 10 min at 70°C Neutralize with 1% acetic acid 80%

Soap for 10 min at 95°C Pale to medium shades: soap once, with 2 g/l CIBAPON R and
2-3 g/l CIBAFLUID C
Soap for 10 min at 95°C Dark shades: soap twice, with 2 g/l CIBAPON R and 2-3 g/l
CIBAFLUID C
Rinse for 10 min at 70°C

Rinse for 10 min at 50°C Rinse once if liquor ratio is 10:1 or above. Rinse twice if liquor ratio is
below 10:1 or intermittent / overflow rinse with 10 l water / kg fabric
if required:
Aftertreat for 20 min at 40°C Recommended for deep shades (approx. 1.5-2 SD), can be
+ 2% CIBAFIX ECO or TINOFIX FRD combined with softeners
(pH 6 with acetic acid)
Minimum salt = cost saving

Conventional reactive dye CIBACRON LS
Production / day : 10’000 kg COTTON 10’000 kg COTTON
Liquor ratio : 15 :1 15 : 1
Amount of liquor : 150’000 litres 150’000 litres
Amount of salt g/l : 80 g/l 20 g/l
Total amount of salt / day : 12’000 kg 3’000 kg
Total amount of salt / year : 3’000’000 kg 750’000 kg
Salt costs / year :
Common salt (US$ 0.10/kg) 300’000 US$ 75’000 US$
Glauber's salt (US$ 0.20/kg) 600’000 US$ 150’000 US$
Contribution of salt addition to Approximately:
recipe costs : 10 - 20 % lower

Lyocell
7.2 Dyeing with CIBACRON F / FN dyes
CIBACRON FN: technically superior dyes with added value
Customer benefits
Increased productivity
F due to excellent washing-off properties
Perfect reproducibility of the dyeings

F due to excellent compatibility of the dyes
Reliable wet fastness

F due to easy washing-off and good linkage stability, especially under
alkaline conditions
Ecologically superior
F less colour in the waste water due to high fixation; environmentally safe
products
Improved cost effectiveness

F due to better build-up on Lyocell

F due to crosslinking behaviour of the bireactive dyes, resulting in improved
fabric appearance and reproducibility of the desired effects

Lyocell
Dye selection
CIBACRON F CIBACRON FN
Bireactive dyes for:
Monoreactive dyes * easy washing off
* reduced fibrillation
Yellow F-4G Yellow FN-2R

Orange F-BR Orange FN-R
Red FN-3G
Red FN-R
Red FN-2BL
Brilliant Blue FN-G
Navy F-G Blue FN-R
Black F-2B Navy FN-B
Trichromatic Combinations
Standard trichromatic system for medium shades
Yellow FN-2R Red FN-3G Blue FN-R
Red FN-R Navy FN-B

For pale to medium shades with very good light fastness
Yellow FN-2R Orange F-BR Red FN-2BL Blue FN-R

For scarlet / red shades
Rot FN-3G
Yellow FN-2R Orange FN-R Red FN-R

Brill. Blue Green Crimson
Brill. Blue FN-G Yellow F-4G Red FN-R

F due to crosslinking behaviour of the bi or trireactive CIBACRON FN dyes, resulting in improved fabric
appearance and reproducibility of the desired effects

Lyocell
CIBACRON F / FN dyeing method
60°C method / soda ash
°C
90
80
70
60
50
40
0 10 20 30 40 50 60 70 80 90
min
addition of addition of salt addition of
auxiliaries soda ash
dye
* Choice of dyeing temperature, depending on special fabric conditions
Salt and alkali recommendations:

Liquor ratio below 10:1
dye % < 0.5 0.5 - 1.0 1.0 - 2.0 2.0 - 3.0 3.0 - 4.0 4.0 - 5.0 > 5.0
salt g/l 10 - 20 20 - 30 30 - 40 40 - 50 50 - 60 60 - 70 80
soda ash g/l 7.5 - 10 10 10 - 12.5 - 15 - 20 20 20
12.5 15
Liquor ratio above 10:1

dye % < 0.5 0.5 - 1.0 1.0 - 2.0 2.0 - 3.0 3.0 - 4.0 4.0 - 5.0 > 5.0
salt g/l 20 - 30 30 - 40 40 - 50 50 - 60 60 - 70 70 - 80 90
soda ash g/l 6-8 8 8 - 11 11 - 14 14 - 15 15 15

Lyocell
Washing off
Procedures Notes
Rinse for 10 min at 50°C Rinse once if liquor ratio is 10:1 / Overflow or
intermittent rinse if liquor ratio is below 10:1
Neutralize for 10 min at 50°C With 0.7 - 1.0 % acetic acid 80%
Soap for 15 min at 90°C 2-3 g/l CIBAFLUID C, addition of 1-2 g/l CIBAPON
R recommended if hard water is used
Rinse for 10 min at 50°C
Soften as usual or refill with

warm water (50°C) and unload
Easy washing off with CIBACRON FN
High fixation Medium substantivity, good

diffusion
⇓ ⇓
Less dye in the effluent Unfixed dyes are easier to
remove, less water
⇓
Less water, time, energy

Lyocell
8. Dyeing with Ciba SOLOPHENYL dyes
SOLOPHENYL
Flavine 7GFE 500% Violet 4BLE 250%
Yellow GLE Blue FGLE 220%
Yellow ARLE 154% Blue TLE
Orange ARLE 220% Blue GL 250%
Orange TGL 182% Blue BFF
Brown AGL Blue 4GL 250%
Brown RL 130% Turquoise BRLE 400%
Scarlet BNLE 200% Green BLE 155%
Red 4GE Green 4GE
Red 2B Navy BLE 250%
Red 3BL Grey 4GLE 300%
Red 7BE Black GN 250%
Pink B 145% Black FGE 600% / liq. 150%
Bordeaux 3BLE

Lyocell
Standard recommendation
Yellow GLE or Yellow ARLE
Scarlet BNLE or Bordeaux 3BLE
Blue FGLE
For high light fastness (*)

Yellow ARLE Brown RL Blue TLE***
Orange TGL Bordeaux 3BLE*** Turquoise BRLE
Orange ARLE*** Violet 4BLE Navy BLE
Brown AGL Green 4GE** Grey 4GLE
Brilliant green shades

Green 4GE** Green BLE**
Turquoise BRLE Flavine 7GFE
Yellow GLE
Dark and forest green shades

Green 4GE** Green BLE**
Yellow ARLE Orange ARLE
Scarlet BNLE Blue FGLE
Violet and bordeaux shades

Violet 4BLE Bordeaux 3BLE
Red 7BE Blue TLE
Blue FGLE
Royal Blue
Blue BFF Turquoise BRLE
* TINOFIX FRD preferred

** Basic components (basic components for brown shades = Brown AGL / RL 130%)
*** Main trichromatic recommendation

Lyocell
Standard method
°C
100
80
60
40
20
0
0 10 50 95 115 130 min
A,B C (1/5) C (4/5)
A auxiliaries 1 g/l IRGASOL CO new or CIBACEL DBC

0.5 g/l ALBATEX FFO or CIBAFLOW JET
3 g/l CIBAFLUID C
B x % SOLOPHENYL dye
C Glauber’s salt in 2 portions ( 1/5 and 4/5 )
=> rinse cold, 2 x 10 min (increased rinsing temperature conceivable to
improve running properties => prevention of wet rigidity of the fabric)
=> aftertreatment if necessary
When dyeing with SOLOPHENYL Black FGE, add soda at the start (pH 8-9)
Required amount of Glauber’s salt
Dye (%) Group 1 (g/l) Group 2 (g/l)

0.05 - 0.10 1-2 5-7
0.10 - 0.25 2-5 7 - 10
0.25 - 0.50 5 - 7.5 10 - 15
0.50 - 0.75 7.5 - 10 15 - 20
0.75 - 1.00 10 - 15 20 - 30
1.00 - 1.25 15 - 17.5 30 - 35
1.25 - 1.50 17.5 - 20 35 - 40
> 1.5 20 - 25 40
Aftertreatment with SOLFIX E Aftertreatment with CIBAFIX ECO or

TINOFIX FRD
100
°C
A y% SOLFIX E (max. 5%) °C
60 A 1-3% CIBAFIX ECO
80 y= 0.5% + 2 x dye amount 50 or TINOFIX FRD,
40
60 concentration 30
adjust pH to 6-6.5
40 B 2 ml/l caustic soda 20
20 66°Tw (36°Bé) 10
A B 0
0 0 10 40 min
0 10 25 55 min A

Lyocell
9. Cold-pad-batch dyeing with CIBACRON C

Dye Selection:
CIBACRON C
Yellow C-5G Red C-R
Yellow C-R-01 Red C-2BL
Yellow C-2R Blue C-R
Orange C-3R Navy C-R
Orange C-RN Navy C-B
Scarlet C-6G Black C-NN
Red C-2G Black C-2R
Red C-GR
additional dyes
Orange BR
Blue 4R Turquoise GN
Standard combination
Yellow C-R-01
Red C-R (Red C-2G for deep red shades)
Orange C-3R / Blue C-R / Navy C-B
Combination for high light fastness
Yellow C-2R / Orange BR
Red C-2BL / Blue C-R
Alkali recommendation
Dye concentration g/l up to 10 20 30 40 50 60 70 and above
Na-silicate 72°Tw (38°Bé) ml/l 70 70 70 70 70 70 70
caustic soda 66°Tw (36°Bé) ml/l 6 9 12 15 18 21 24
Recipe: x g/l CIBACRON C dye

1-2 g/l CIBAFLOW PAD (de-aeration, wetting)
Fixation time: 12 - 20 h
Fixation temperature: 25 - 30 °C

F due to crosslinking behaviour of the bi or trireactive CIBACRON C dyes, resulting in improved fabric
appearance and reproducibility of the desired effects
F For further information, please contact CTS CEL Dyeing in Basle / Switzerland

Lyocell
10. Printing
Since Lyocell fibres tend to behave more like traditional viscose than cotton in application
and fastness levels are the same as on viscose, we recommend:
u using the same dyestuffs

u using the same recipes as for other cellulosic fibres
u fixation conditions are the same, i.e. the fibre requires higher humidity during
steaming, like viscose
u avoiding dry heat setting
As the fibre is well-known for its tendency to fibrillate, care must be taken to ensure that
the various processing operations are as gentle as possible.
The critical stage is the washing-off process. All mechanical stress must be avoided, i.e. the
prints must only be washed off in open-width washing machines. The material is very stiff
in the wet state and crease marks (locally excessive fibrillation) tend to form when it is
folded. It is thus advisable to roll it up after the respective operations.
To prevent subsequent fibrillation, as could occur, for example, during household
laundering, the goods must be suitably aftertreated with resins as recommended for dyed
goods (see chapter 11).
F for further information please contact CTS Printing in Basle (Switzerland)!
11. Peachskin effect / resination

12. Reducing fibrillation

Most cellulosic fibres have a tendency to fibrillation, the different degrees of which are
shown in the table below:
Lyocell Polynosic Cupro Cotton Viscose HWM
(CLY) (CMD) (CUP) (CO) (CV) (CMD)
Degree of fibrillation
0 = minimal 4-6 3 2-3 2 1 1
One potential side effect of fibrillation is a substantial increase in the textile surface area.
Light directed onto the substrate surface is thus reflected more diffusely, resulting in an
optically paler, here greyer, appearance of the Lyocell fabric.

Lyocell
These special fibre properties and processing conditions apply particularly to goods in rope form and
those intended for the garment sector. This means that the fibre areas subject to friction during wet
processing (textile to textile and/or textile to metal) usually have higher degree of fibrillation than the
inner (protected) areas. It follows that this tendency to local additional fibrillation depends among other
things on the general degree of fibre fibrillation.
An overall distinction must be made between processing-related fibrillation and that which occurs
during wear. Whereas the latter can in principle be controlled through resin finishing, fibrillation that
occurs during wet processing (for example during dyeing) could not hitherto be controlled.
Extensive tests with resin finishing (including on fabrics of Lyocell fibres) have shown that crosslinking
reactions inhibit fibrillation. As this crosslinking effect is virtually permanent, stability to fibrillation is
retained during household laundering.
A comprehensive study has revealed that a very specific type of bi- or polyfunctional reactive dye (for
example CIBACRON) causes an interfibrillar crosslinking reaction. A dye molecule with its reactive
groups is covalently bonded to at least two adjacent cellulose chains, thus crosslinking them with one
another. This reduces, sometimes substantially, the fibrillation tendency, both during wet processing
and on the end product, even after repeated washing. Thus the use of such dyes of the CIBACRON type
permanently reduces the fibrillation tendency of cellulosic fibres, starting in the dye fixation phase.
In addition to high fixation, these dyes are highly dependable in processing; the material is subjected to
constant mechanical loads in the dyeing machine and the degree of fibrillation during dyeing can
therefore be closely controlled. This results in high batch-to-batch reproducibility, as borne out by
extensive bulk trials.
However, a comparison of the different fabrics shows that although identical dyeing conditions result in
the same shade, the degree of fibrillation can vary. This is because the tendency to fibrillation also
depends on physical parameters of the textile, for example:
* thread fineness
* yarn twist Lyocell fibre
* fabric type (woven, knitted
* fabric density
* weave type
Interfibrilar spaces
Further factors affecting Possible position for
fibrillation include: cross-linking agent
* pH
* liquor ratio
* temperature Lyocell fibre
* degree of primary fibrillation Possible position for bi-
* degree of enzymatic defibrillation or multifunctional dye
* degree of secondary fibrillation
* mechanical conditions /
lubricants, etc.

Lyocell
Wet abrasion (Martindale)
CIBACRON Red F-B

1800
1600
1400
No. of revs.
1200
1000 785 780 780 775 775 775

800
600
0,5 % 1% 2% 4.50% 6% 8%
CIBACRON Red C-2G

1800
1560
1600 1480
1350
1400 1144
No. of revs.
1200
900 981
1000
800
600
0,5 % 1% 2% 4.50% 6% 8%
Conclusions
Further investigations are needed to determine the extent to which reactive dyes with a
crosslinking action can partly replace resin finishing (where required). As the degree of
crosslinking by multireactive dyes also depends on dye concentration (the deeper the
shade, the higher the degree of crosslinking), ways of achieving an equivalent degree of
crosslinking had to be sought for pale shades or to prevent fibrillation generally (colourless
crosslinking agent).
The crucial point, however, is to be able to control as closely as possible the degree of
fibrillation during dyeing.
It has also been proved that there is no shade change with those CIBACRON dyes in
question, even on subsequent enzymatic defibrillation.
Thus the reproducibility is high, including under critical conditions.

Lyocell
13. Machinery requirements for dyeing and finishing Lyocell items
Dyeing machines
Thies Luft-roto Thies GmbH

Thies Air-stream Thies GmbH
Then Airflow AFS /AFT Then Maschinen- und Apparatebau GmbH
ICBT Alizée ICBT-Madinox
Krantz Aero-dye Krantz Textiltechnik
Softglider Scholl AG
Air-Jet Hisaka Works Co, LTD
Circular Air-Jet Vald. Henriksen a/s
Airtint EVO ATYC
Airsoft HT Longclose LTD
Air-Jet-Scirocco Alliance
Air-water Flow 800 LAIP
Aero-Dye AM-OHD ACME Taiwan
Antares Brazzoli
Air Jet HT MCS
Tumbler
Thies roto-tumbler Thies GmbH

Biancalani Aero 1000 Biancalani & C.S.N.C.
ICBT Zephyr ICBT-Madinox
Then Airflow AFS with tumbler module Then Maschinen- und Apparatebau GmbH
Krantz Areo-dye with tumbler module Krantz Textiltechnik
Airtint with tumbler module ATYC

Lyocell
14. Selection of auxiliaries

Auxiliaries for aftertreatment
PRODUCTS EFFECTS BENEFITS
Ciba - wet fastness improver - formaldehyde-free


T I N O F I X F R D - cationic - prevents migration after dyeing
1 - 3%* - protects dye/fibre linkage of reactive dyes
against acid hydrolysis and thermocracking
- promotes good wash fastness up to 40°C
- little effect on light fastness and shade
- no adverse effect on handle
Ciba - wet fastness improver - special fixing agent that reacts with
SOLFIX E for SOLOPHENYL cellulosic fibres; applied by exhaustion
0-5% dyes - suitable for use with selected SOLOPHENYL
dyes in the SOLFIX system
- cationic
- high level of wet fastness, ensures a rating
of 4 at up to 2/3 SD in ISO 60°C wash test
C I B A F I X  E C O - wet fastness improver - formaldehyde-free
1-3% - cationic - prevents migration after dyeing
- protects dye/fibre linkage of reactive dyes
against acid hydrolysis and thermocracking
- promotes good wash fastness up to 40°C
- no adverse effect on handle
* Amount required depends on specific conditions, e.g. liquor circulation and composition of the dyebaths.

Lyocell
Penetrating / de-aerating / defoaming
PRODUCT EFFECTS BENEFITS
- penetration - silicone-containing product with de-aerating effect

Ciba and durable antifoam action
accelerant
ALBATEX FFC - very stable to high alkali and electrolyte
- slightly anionic
0.1 - 0.5 g/l* concentrations
- ideal for machines with short-liquor or air-stream
technology
- penetration - silicone-free product with de-aerating effect and
Ciba antifoam properties
accelerant
ALBATEX FFO - very stable to high alkali and electrolyte
- anionic
0.3 - 1 g/l* concentrations
- suitable for all types of equipment, especially jets
and overflow machines
- APEO and solvent free product with durable
C I B A F L O W  J E T - penetration antifoam action
0.1 - 0.5 g/l* accelerant
- anionic - very stable to high alkali and electrolyte
concentrations
- specially recommended for jets and overflow
machines with short-liquor or air-stream
technology
- good shear stability
high
wetting/de-aerating
ALBATEX FFC
ALBATEX FFO
CIBAFLOW JET
low
low high
foam suppressing
* Amount required depends on specific conditions, e.g. liquor circulation and composition of the dyebaths.

Lyocell
Specific products
Ciba - protective colloid - avoids precipitation of Ca, Mg in the water or on

- wetting effect the textile
IRGASOL CO - promotes levelness of the dyeing and improves the
- dispersing effect
new appearance of the dyed goods
- Ca inactivation - keeps impurities from non or poorly pre-treated
0.5 - 2 g/l* - anionic cotton in stable dispersion
- permits dyeing of grey state cotton with good
fastness properties
- reduction - prevents reduction of reactive dyes
Ciba - protects direct dyes against hydrolysis in HT dyeing
LYOPRINT protectant cycles
RG - anionic
1 - 3 g/l*
- dyebath conditioner: prevents precipitation of Ca,
C I B A C E L  D B C - dispersing agent Mg in the water or on the textile
0.5 - 2 g/l* - anionic - promotes levelness of the dyeing and improves the
appearance of the dyed goods
- prevents shade changes resulting from heavy metal
ions in the dyebath
- reduces creasing in piece dyeing
C I B A F L U I D  C - lubricant - markedly reduced textile-to-textile friction
0.5 - 2 g/l - anionic / nonionic
- prevents cracks and abrasion marks
- no adverse effect on the stability of the dyebath
- no retarding effect
Soaping

CIBAPON R - washing agent - speeds up release and outward diffusion of dye
- anionic hydrolysates, including in hard water
0.5 - 2 g/l - prevents renewed uptake of dye hydrolysate
- inactivates water hardness ions and ensures
maximum fastness properties
- low foaming
* Amount required depends on specific conditions, e.g. liquor circulation and composition of the dyebaths

Lyocell
15. Potential process route

1. Singeing
Desizing / Pretreatment (open width preferred)
Second singeing (if necessary)
2. Primary fibrillation (i.e. on Airflow, Luft roto, Softglider or similar machines)

⇒ 2-4 g/l CIBAFLUID C
⇒ fill and adjust to 60°C
⇒ feed in at 60°C (to prevent wet rigidity)
⇒ 2-4 g/l soda ash (or caustic soda)
⇒ increase temperature to 80-95°C (120°C if necessary)
⇒ run for 60-120 minutes
⇒ turnover time: 60-70 seconds
⇒ drain
⇒ rinse to neutralize (if possible overflow)
3. Enzymatic defibrillation of woven fabrics (*)

3-5 % TINOZYM 7603 (acid cellulase)
2-3 g/l DIPHASOL LJ (lubricant)
⇒ * liquor ratio 5:1 - 10:1
* set pH at 4.5-5.5 (buffer preferred)
* add chemicals
* raise temp. to 45-55°C
* run for 45 to 90 minutes
⇒ * denaturate (10 min; 85°C or pH 9-10)
(30-45 min recommended to improve the peachskin effect)
* drain
* rinse (if possible overflow)
4. Exhaust dyeing (machines as above)

CIBACRON LS; CIBACRON FN F exhaust dyeing gives a softer handle than pad dyeing
SOLOPHENYL
⇒ important: full primary fibrillation is necessary in order to prevent
excessive post fibrillation during dyeing
⇒ start at 60°C
Dyebath lubricants should be used. Secondary or ‘short fibrillation’ during the dyeing process
will help, in conjunction with mechanical aftertreatment to generate the desired peach skin
effect.
or: Dyeing cold pad batch with CIBACRON C
⇒ in most cases the C method gives improved penetration
⇒ stiffer handle, loss of peachskin effect
⇒ but no post fibrillation can occur
(*) The enzymatic defibrillation of knit goods should take place subsequent to the exhaust dyeing process

Lyocell
5. Possibly second enzymatic defibrillation (clean surface)

This may have to be carried out on some fabrics, if there is excessive post fibrillation obtained during jet
dyeing or for a clean surface effect. The same procedure should be followed as described in part 3.
6. Soften (peachskin effect)

30 g/l or 3.0% MEGASOFT JET ⇒ process conditions depend on application method
7. Stabilizing (pad finishing - resination)

(to maintain a clean surface after repeated washing)
20-40 g/l KNITTEX FEL
6-12 g/l KNITTEX CAT.MO
20 g/l ULTRATEX FMK
20 g/l TURPEX ACN
or alternatively:
60 g/l KNITTEX FRF (as formaldehyde-free finish)
* dry to approximately 20% residual moisture
* cure
8. Secondary fibrillation on Aero 1000 or HT-Roto-Tumbler

(or similar machines)
Potential problems:
* to obtain an evenly fibrillation (jet)
* Lyocell fibres tend to stiffen in the wet state (running marks, especially on heavy fabrics)
* to obtain an evenly defibrillation
* post fibrillation can occur during rope dyeing
(if primary fibrillation has not been completed)
⇒ higher costs
* if crosslinking follows tumbler treatment, the handle will be stiffer and the desired
peachskin effect may be destroyed
* generally unsatisfactory reproducibility of the effects
There are alternative or optimized processes for reducing fibrillation:

* pretreatment at open width (desizing, pad-batch)
* primary fibrillation and enzymatic defibrillation as described above / application of
colourless crosslinking agent either without primary fibrillation and enzymatic
defibrillation or after those (depended on the desired effects)
* dyeing with selected CIBACRON FN or LS dyes (interfibrillary crosslinking)
or: * cold pad-batch dyeing with CIBACRON C dyes
=> washing-off at open width
* crosslinking (resination)
* jet treatment (softening)
* tumbler treatment (Aero 1000 or HT-Roto-Tumbler or similar machines)

Lyocell
16. Bulk trial dyeing of Lyocell

Thies Luft-roto
Migration method / Soda
ash
100 Dark brown :
60 min
90 1.5 % CIBACRON Yellow LS-R
80 C
30 min 2°C/min 2.2 % CIBACRON Scarlet LS-2G
70
75 min 2.5 % CIBACRON Green LS-3B
2°C/min
45 min
60
D 3.0 g/l CIBAFLUID C
50 1.0 g/l CIBACEL DBC
40 30.0 g/l Glauber’s salt
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
A E 15.0 g/l soda ash
B
Salt and alkali recommendations

B salt g/l 10 10 - 15 15 - 17.5 17.5 - 20 20 - 25 30
D soda ash g/l 10 10 10 - 11 11 - 12 12 - 13.5 15
E - Washing off
Operations Remarks
Rinse 10 min at 50°C Rinse once for liquor ratio 10:1 or above. Rinse twice for liquor ratio
below 10:1; or intermittent / overflow rinse (10 l water / kg fabric)
Rinse 10 min at 70°C Neutralize with 1% acetic acid 80%
Soap 10 min. at 95°C Soap once for pale to medium shades with 2 g/l CIBAPON R and
2-3 g/l CIBAFLUID C
Soap 10 min. at 95°C Soap twice for dark shades with 2 g/l CIBAPON R and 2-3 g/l
CIBAFLUID C
Rinse 10 min. at 70°C
Rinse 10 min. cold Rinse once for liquor ratio 10:1 or above; twice for LR below 10:1, or
intermittent / overflow (10 l water / kg fabric)
Lyocell Batch 110.-kg Width 150 cm Length 300 m Liquor ratio 1:6
Nm 30x1 Twill Tube 1 ∆P 0,6 bar Turnover time 47 sec. Speed 383 m/min
Results Notes Recommendations

perfect lab to bulk transfer few crease marks; no rope marks, primary 2nd enzyme treatment after dyeing:
(LR. from 1:15 to1:6 !), fibrillation and enzyme cleaning not sufficient => clean surface, practically no shade
levelness OK prior dyeing => many fibrils & fluffs deviations owing to the enzyme
treatment

Lyocell
For further details, please contact

your local Ciba Specialty Chemicals Inc.
organization.
This Technical Information is based on the present

state of our knowledge. It shows without liability
on our part the uses to which our products can be
put.
Ciba Specialty Chemicals Inc. CTS EXHAUST Fax 061 / 636 7983
Klybeckstrasse 141 CO 4.5
CH-4002 Basle
Switzerland
Copyright © 1999 Ciba Specialty Chemicals Inc. All rights reserved. Replace 1X4007.E
All product names in capital letters are either registered or pending trademarks and property of Ciba Specialty Chemicals.
IMPORTANT: The following supersedes Buyer’s documents. SELLER MAKES NO REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, INCLUDING OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. No statements herein are to be construed as inducements to infringe any relevant patent.
Under no circumstances shall Seller be liable for incidental, consequential or indirect damages for alleged negligence, breach of warranty, strict liability,
tort or contract arising in connection with the product(s). Buyer’s sole remedy and Seller’s sole liability for any claims shall be Buyer’s purchase price.
Data and results are based on controlled or lab work and must be confirmed by Buyer by testing for its intended conditions of use. The product(s) has
not been tested for, and is therefore not recommended for, uses for which prolonged contact with mucous membranes, abraded skin, or blood is
intended; or for uses for which implantation within the human body is intended.
Please note that products may differ from country to country. If you have any queries, kindly contact your local Ciba Specialty Chemicals representative.
Further information at web site: http://www.cibasc-colors.com.
Ciba Specialty Chemicals Colors division is a member of:
(Ecological and Toxicological Association of Dyes and Organic Pigments Manufacturers)

1X4009.E- Nov-99, Printed in Switzerland.

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Ciba Specialty Chemicals Inc.

Value beyond chemistry

A guide to pretreatment, dyeing and finishing

Page 1, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

2. The NMMO process 4

3. Lyocell fibre properties 6

4. Fibrillation / definition / influencing factors / assessment 7

6. Primary fibrillation / enzymatic defibrillation 8

7.1 Dyeing with CIBACRON LS dyes (method, dye selection) 9

7.2 Dyeing with CIBACRON FN dyes (method, dye selection) 11

8. Dyeing with Ciba SOLOPHENYL dyes (method, dye selection) 15

9. Pad-batch dyeing with CIBACRON C 18

11. Peachskin effect / resination 19

12. Reducing fibrillation 19

13. Machinery requirements for dyeing and finishing Lyocell items 22

14. Selection of auxiliaries 23

15. Potential process route 26

16. Bulk trial with Lyocell / CIBACRON LS 28

Page 2, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

1. Lyocell fibres - definition / market position

At present well-known Lyocell fibres produced by the NMMO process are:

The market segments currently being studied are:

Page 3, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

2. The NMMO process

(N - methyl morpholine N - oxide)

♦ high cellulose dissolving power suitable for the preparation of a solution

♦ promotion of useful fibre properties

♦ low environmental pollution

Page 4, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

XANTHOGENATE - PROCESS NMMO - Process

Spinning bath Spinning bath

Dry Calcination Dry

Page 5, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

3. Lyocell fibre properties

Page 6, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

Page 7, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

6. Primary fibrillation / enzymatic defibrillation

Page 8, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

7.1 Dyeing with CIBACRON LS dyes

Yellow LS-R For combination shades

Red LS-B For combination shades

Black LS-N Tinctorially strong, deep black dye

Page 9, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

Washing off and aftertreatment

Rinse for 10 min at 70°C Neutralize with 1% acetic acid 80%

Rinse for 10 min at 70°C

Minimum salt = cost saving

Page 10, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

7.2 Dyeing with CIBACRON F / FN dyes

CIBACRON FN: technically superior dyes with added value

Perfect reproducibility of the dyeings

Reliable wet fastness

Improved cost effectiveness

Reduced fibrillation tendency

Page 11, Ciba Specialty Chemicals, 1X4009.E / Nov.-99

Yellow F-4G Yellow FN-2R

Yellow FN-2R Red FN-3G Blue FN-R

Red FN-R Navy FN-B

Yellow FN-2R Orange F-BR Red FN-2BL Blue FN-R