**6. Experimental**

62 Natural Dyes

the required 3–5 hours wetting of material with water before dyeing could be greatly reduced by wetting in a bath by specially made wetting agent, and this or another agent could also be added into the dyeing bath. The ineffective use of natural dyes was already discussed above. The majority of dyes ceases as effluents in sewer. The mordanting salts do not have affinity to the fibers and therefore only a small part of them is bounded with fibers, and after dyeing and final rinsing all the remnants are carried off by water. What about the idea of storing the mordanting baths for future use? While logical, the number and volume of stock reservoirs (and place in dye house) make it an unpractical possibility. Naturally, serious conception-questions follow from this. Should "natural dyeing" remain as something principally untouchable whose traditional originality must be safe-guarded at any costs, or are we going to consider this natural raw-material source as an ecologically favorable supplement to synthetic colourants? or, can we synthesize the methodologies of "natural dyeing" with the research and application processes of modern dyeing technology? Nevertheless, both natural dyeing and modern dyeing technology can coexist. In any case,

 the consequent minimization of concentration of natural dyes and mordants, the shortening of operating times, i.e., to save energy and productivity, and

are known. The following two principles are important for our purpose:

After both dye fixation methods water rinsing follows repeatedly.

unevenness),

24 hours.

a. fixation by drying*,* the so-called pad-dry method, the process is rapid but requires a reliably functional drying device (an excellently even -drying effect breadth-ways and cross-ways in the fabric is necessary, otherwise it may result in colour depreciation and

b. fixation by batching of the padded goods at room or slightly increased temperature, now known as the pad-batch method. The padded and rolled goods are wrapped up in an airtight plastic sheet so that no selvedge drying occurs during storage, which lasts 8–

All these can be assured by the padding (pad) technologies, in which the liquor ratio (weight of textiles: bath) is about one order lower (≤1:1) than the common exhaustion (bath or batch) dyeing methods. The padding technologies are particularly advantageous to dyeing with the low-affinity products, because the dye affinity to fiber by padding is unnecessary (in phase of the dye deposition on the fabric). The dye bath is cloth "padded": mechanically applied by the rapid passage through the small padding trough*,* the intensive squeezing between expression rollers follows immediately. The process of padding is continuous and very rapid. It depends on the arrangement of the following dye fixation if the total procedure is continuous or semi continuous. The dye bath by padding is about one order higher than by the common dyeing from the "long bath" (the so-called exhaustion methods), in which the dyestuff exhausts on the fiber in consequence to its affinity to the fiber. The higher padding bath concentration results in more rapid dye diffusion in fiber during the next fixation operation. Much smaller bath volume (related to the fiber unit) causes the higher dye exploitation. In the case of natural dyes, the dye fixation is based on the reaction (see also Agarwal and Patel) (Agarwal & Patel, 2001) with the salts of complexforming metals-mordants in the same or next bath-or the textile can be pre-metalized with mordant (this pre-mordanting is carried out from the long bath-the large non-effectiveness is mentioned above*.* Therefore, we also experimented with pad-dry and pad-batch principle at this operation). In semi continuous dyeing technology, several methods of dye fixation

we are trying to explore the second of the following:

the maximal efficient use of dye and mordanting baths.

The research focused on the properties of pad-dyeing techniques, we investigated the dyeing and ultraviolet (UV) protection properties of wool fabric using an aqueous extract of eucalyptus leaves as the natural dye. Different factors affecting dyeing ability were also thoroughly investigated.

The following laboratory-grade mordants were used: aluminium potassium sulfate dodecahydrate (AlK(SO4)2.12H2O), ferrous (II) sulfate heptahydrate (FeSO4.7H2O), copper (II) sulfate pentahydrate (CuSO4.5H2O) and stannous chloride pentahydrate (SnCl2.5H2O). The anionic wetting agent, Altaran S8 (sodium alkylsulfate), and soaping agent, Syntapon ABA, were supplied by Chemotex Decin, Czech Republic.

The mordanting and dyeing processes were carried out in a two-bowl padding mangle machine (Mathis, Typ-Nr. HVF.69805). A drying machine (Mathis Labdryer, Typ-Nr. LTE-2992) was used for the drying of the dyed fabrics. A GBC UV/VIS 916 (Australia) spectrophotometer and a Datacolor 3890 were employed for the absorbance and colour strength measurements, respectively. The transmittance and ultraviolet protection factor (UPF) values were measured by a Shimadzu UV3101 PC UV-VIS-NIR scanning spectrophotometer in the 190 nm to2100 nm range.

Fresh eucalyptus leaves (*E. Camaldulensis)* were dried in sunlight for one month and crumbled using a blender, and then were used as the raw material for dye extraction, which was achieved by the reflux technique: 70 g of crumbled eucalyptus leaves was mixed with one liter of distilled water and refluxed for one hour. The dye solution was filtered, evaporated, and dried under reduced pressure using a rotary evaporator. The crude dye extract of the eucalyptus leaves was then crumbled with a blender and used for obtaining the standard calibration curve. The dilution of the eucalyptus leaf extract gives a relatively clear solution with a linear dependence on the concentration absorbance, an absorption peak (λmax) at 262 nm (Yarosh et al., 2001). The concentration of 20 g/l was calculated from a standard curve between concentrations of eucalyptus leaf dye solutions versus absorbance at the wavelength mentioned.

The pre-mordanting methods, wool fabrics were immersed in each mordant solution with anionic wetting agent and padded on a two-bowl padding mangle at 80% pick up. Next, the mordanted sample was impregnated in each eucalyptus dye concentration. After padding for 2 seconds the samples were dried at 90°C for 5 minutes for a pad-dry technique. Under the cold pad-batch dyeing technique, the padded fabric was rolled on a glass rod with a plastic sheet wrapped around the rolled fabric. Then it was kept at room temperature for 24 hours. After the dyeing step, the samples were washed in 1 g/l of a soaping agent, Syntapon ABA, at 80°C for 5 minutes, then air dried at room temperature. For the simultaneous mordanting (metamordanting) method (i.e. dyeing in the presence of mordants), the fabrics were immersed in a bath containing a mordant and the dye extract at room temperature and padded on a two-bowl padding mangle at 80% pick up. The processing of pad-dry, pad-batch and soaping were the same as above mention. In the post-mordanting method, the fabrics were immersed in each eucalyptus dye concentration and without mordant, followed by padded on a two-bowl padding mangle at 80% pick up. Then the padded samples were padded by mordanting. Further processing was the same as described in the pre-mordanting method.

The colour strength (*K/S*) and CIELAB of the dyed samples were evaluated using a spectrophotometer (Datacolor 3890). All measured sample showed the maximum absorption wavelength (λmax) value at 400 nm. The *K/S* is a function of colour depth and is

Natural Dye from Eucalyptus Leaves and

strength than without mordant.

Dye Conc. (g/l)

*K/S L\* a\* b\** 

Type of mordant

Without mordant

AlK(SO4)2 (Al)

> CuSO4 (Cu)

FeSO4 (Fe)

SnCl2 (Sn)

of the dye

Note: 1 20g/l dye concentration

Application for Wool Fabric Dyeing by Using Padding Techniques 65

λmax value at 400 nm. Table 1 to Table 3 show CIELAB *L\**, *a\**, *b\** values for the wool fabric dyed with different mordants by three mordanting methods (pre-mordanting, simultaneous mordanting and post-mordanting) and using two padding techniques, namely the pad-batch and pad-dry techniques. *L\**, *a\**, *b\** refer to the three axes of the CIELAB system. The *L\** value indicates perceived lightness in CIELAB colour space. The *L\** scale run from 0 (black) to 100 (white); the higher the *L\** reading the lighter colour. The *a\** value indicates red (*+a\**) and green (*-a\**) while the *b\** value indicates yellow (*+b\*)* and blue (*-b\*)* (Sarkar & Seal, 2003 ; Giles,1974; Duff & Sinclair,1989). It can be observed that the *K/S* values increase with an increase of dye concentration. Little difference between the two padding techniques utilized for the wool fabric dyes by three mordanting methods, except wool fabrics mordanted with copper sulfate whose gave a high *K/S* values on the pad-batch technique than pad-dry technique. In all cases ferrous sulfate mordant yielded the best dyeing results, and the next good result was obtained in the order of copper sulfate, stannous chloride and alum. As observed from the *K/S* values, in the case of wool fabrics dyed with alum by using post-mordanting method gave lower colour

Pad-batch on wool fabric Pad-dry on wool fabric

sample *K/S L\* a\* b\** 

1Dyed sample

1Dyed

5 1.50 76.1 3.5 14.2 1.13 77.7 3.5 12.0 10 1.60 76.0 3.5 15.0 1.54 76.3 3.6 14.1

20 1.86 75.4 3.5 15.8 1.86 75.9 3.4 15.8

5 1.44 79.0 0.4 19.1 1.36 79.6 0.1 20.3 10 1.70 77.6 0.1 19.3 1.45 78.8 0.2 19.7

20 1.75 75.2 0.8 20.4 1.70 76.5 0.8 19.0

5 2.58 67.2 2.2 20.6 2.02 70.8 2.8 20.0 10 3.36 63.7 2.9 21.3 2.20 69.3 3.1 19.4

20 3.42 63.0 3.3 21.8 2.70 67.1 3.4 20.1

5 2.16 50.9 1.5 0.1 2.66 46.8 2.3 0.4 10 2.94 45.2 1.8 -0.6 3.52 43.1 3.1 0.6

20 4.22 40.0 2.2 -0.6 4.34 38.6 3.4 0.7

5 1.86 84.5 -0.4 26.2 2.14 83.0 -0.3 26.9 10 2.28 83.7 -0.3 28.4 2.25 83.0 -0.4 26.9

20 2.98 81.5 0.5 30.8 2.37 81.6 0.1 26.7

Table 1. Colour value of wool fabric dyed with eucalyptus leaf extract by pre-mordanting and padding techniques, with using 10 g/l of metal mordants at different concentration

calculated by the Kubelka-Munk equation, *K/S = (1-R)2*/*2R*, where R is reflectance, *K* is the sorption coefficient, and *S* is the scattering coefficient.

#### **6.1 Identification of crude eucalyptus extracted dye**

The crude eucalyptus leaf extract dye was characterized by ultraviolet-visible spectroscopy. The crude extraction solution (50 mg/l) was prepared by dissolving in distilled water. The spectrophotometer was scanned from 190 nm to 820 nm to obtain the UV/Visible spectra. The UV-vis spectrum of the crude eucalyptus leaf extract dye in an aqueous solution is presented in Fig. 3. The characteristic spectrum shows absorptions in the 205–210 nm and 250–270 nm regions. Absorption in the 205–210 nm region may be attributed to various chromophores, including the C=C bond of various compounds, the C=O bond of carbonyl compounds, and the benzene ring (probably from aromatic compounds) (Pretsch et al., 2000). Absorption in the 250–270 nm regions may be attributed to the electronic transitions of benzene and its derivatives, which may include various aromatic compounds such as phenolics (Pretsch et al., 2000). It can be observed from Fig. 3 that the dye can absorb radiations in the UV-C region (200–290 nm), the UV-B region (290–320) and the UV-A region (320-400) (Feng et al., 2007).

Fig. 3. UV-VIS spectrum of 50 mg/l crude eucalyptus leaf extract dye in distilled water.

#### **6.2 Dyeing property of wool fabric dyed with eucalyptus leaf extract by using padding techniques by varying quantity of dye concentrations**

The effect of mordanting methods and padding techniques on dyeing of wool fabric with different mordants are shown in Table 1 to Table 3. All measured sample showed the greatest

calculated by the Kubelka-Munk equation, *K/S = (1-R)2*/*2R*, where R is reflectance, *K* is the

The crude eucalyptus leaf extract dye was characterized by ultraviolet-visible spectroscopy. The crude extraction solution (50 mg/l) was prepared by dissolving in distilled water. The spectrophotometer was scanned from 190 nm to 820 nm to obtain the UV/Visible spectra. The UV-vis spectrum of the crude eucalyptus leaf extract dye in an aqueous solution is presented in Fig. 3. The characteristic spectrum shows absorptions in the 205–210 nm and 250–270 nm regions. Absorption in the 205–210 nm region may be attributed to various chromophores, including the C=C bond of various compounds, the C=O bond of carbonyl compounds, and the benzene ring (probably from aromatic compounds) (Pretsch et al., 2000). Absorption in the 250–270 nm regions may be attributed to the electronic transitions of benzene and its derivatives, which may include various aromatic compounds such as phenolics (Pretsch et al., 2000). It can be observed from Fig. 3 that the dye can absorb radiations in the UV-C region (200–290 nm), the UV-B region (290–320) and the UV-A region

sorption coefficient, and *S* is the scattering coefficient.

**6.1 Identification of crude eucalyptus extracted dye** 

(320-400) (Feng et al., 2007).

**0.00**

**200**

**214**

**228**

**242**

**256**

**techniques by varying quantity of dye concentrations** 

**270**

**284**

**298**

**312**

**326**

Fig. 3. UV-VIS spectrum of 50 mg/l crude eucalyptus leaf extract dye in distilled water.

**340**

**6.2 Dyeing property of wool fabric dyed with eucalyptus leaf extract by using padding** 

The effect of mordanting methods and padding techniques on dyeing of wool fabric with different mordants are shown in Table 1 to Table 3. All measured sample showed the greatest

**354**

**Wave length (nm)**

**368**

**382**

**396**

**410**

**424**

**438**

**452**

**466**

**480**

**494**

**0.20**

**0.40**

**0.60**

**0.80**

**1.00**

**Absorbance**

**1.20**

**1.40**

**1.60**

**1.80**

**2.00**

λmax value at 400 nm. Table 1 to Table 3 show CIELAB *L\**, *a\**, *b\** values for the wool fabric dyed with different mordants by three mordanting methods (pre-mordanting, simultaneous mordanting and post-mordanting) and using two padding techniques, namely the pad-batch and pad-dry techniques. *L\**, *a\**, *b\** refer to the three axes of the CIELAB system. The *L\** value indicates perceived lightness in CIELAB colour space. The *L\** scale run from 0 (black) to 100 (white); the higher the *L\** reading the lighter colour. The *a\** value indicates red (*+a\**) and green (*-a\**) while the *b\** value indicates yellow (*+b\*)* and blue (*-b\*)* (Sarkar & Seal, 2003 ; Giles,1974; Duff & Sinclair,1989). It can be observed that the *K/S* values increase with an increase of dye concentration. Little difference between the two padding techniques utilized for the wool fabric dyes by three mordanting methods, except wool fabrics mordanted with copper sulfate whose gave a high *K/S* values on the pad-batch technique than pad-dry technique. In all cases ferrous sulfate mordant yielded the best dyeing results, and the next good result was obtained in the order of copper sulfate, stannous chloride and alum. As observed from the *K/S* values, in the case of wool fabrics dyed with alum by using post-mordanting method gave lower colour strength than without mordant.


Note: 1 20g/l dye concentration

Table 1. Colour value of wool fabric dyed with eucalyptus leaf extract by pre-mordanting and padding techniques, with using 10 g/l of metal mordants at different concentration of the dye

Natural Dye from Eucalyptus Leaves and

*K/S L\* a\* b\** 

Dye Conc. (g/l)

Type of mordant

Without mordant

AlK(SO4)2 (Al)

> CuSO4 (Cu)

FeSO4 (Fe)

SnCl2 (Sn)

the dye

Note: 1 20g/l dye concentration

**batching time on pad-batch** 

fabric was enhanced by using metal mordants.

Application for Wool Fabric Dyeing by Using Padding Techniques 67

1Dyed

5 1.50 76.1 3.5 13.7 1.13 77.7 3.5 12.0 10 1.60 76.0 3.5 15.1 1.54 76.3 3.6 14.1

20 1.86 75.4 3.5 15.7 1.86 75.9 3.4 15.8

5 1.11 81.3 -1.2 19.2 0.93 82.1 0.6 16.9 10 1.23 80.2 -1.0 20.1 1.10 80.8 0.4 18.5

20 1.39 79.3 -0.8 21.4 1.28 79.7 0.2 19.9

5 2.50 66.8 -1.1 19.5 1.84 68.5 0.4 17.3 10 2.81 65.4 -0.1 20.3 2.12 66.8 0.6 18.7

20 3.06 63.7 0.2 20.2 2.87 63.1 1.7 20.2

5 3.18 53.0 1.8 8.4 2.28 55.8 1.5 6.1 10 3.35 50.2 2.0 8.5 2.71 51.1 1.5 3.9

20 3.86 46.7 1.5 2.7 3.13 45.7 1.6 1.0

5 1.54 85.4 -0.3 25.6 1.52 86.6 -0.3 24.8 10 1.90 85.0 -0.2 27.8 1.88 85.1 -0.2 25.7

20 2.05 84.0 -0.1 28.1 2.01 84.1 -0.2 26.6

Table 3. Colour value of wool fabric dyed with eucalyptus leaf extract by post-mordanting and padding techniques, with using 10 g/l of metal mordants at different concentration of

**6.3 Effect of quantity of mordant concentrations, time/ temperature on pad-dry and** 

Table 4 shows the colour values of wool fabric dyed with eucalyptus leaf extract by varying quantity of mordant concentrations. All measured sample showed the greatest λmax value at 400 nm. It can be seen that the *K/S* values increase with an increase of mordant concentration. The dyed uptake values were greater at the higher mordant concentration. This could be attributed to the darkening and dulling of shades due to mordant effect. Little different between the two padding techniques utilized for the study is observed. Wool fabric dyed with eucalyptus leaf extract in the absence mordant showed yellowish brown shades. Comparison of four metal mordants showed that the ferrous sulfate metal mordant gave the highest depth of shade on wool fabric. Thus ferrous sulfate was the best mordant during mordanting method of dyeing. This could be attributed to difference in CIELAB values of the dyed samples. The mordant activity of the five sequences was as follows: Fe > Cu > Al > Sn > without mordanted in wool fabric, the absorption of colour by wool

Pad-batch on wool fabric Pad-dry on wool fabric

sample *K/S L\* a\* b\** 

1Dyed sample

Alum and ferrous sulfate were the best mordant during simultaneous mordanting method of dyeing. However, copper sulfate showed the best mordant during simultaneous mordanting and pre-mordanting method of dyeing. For the *K/S* value on dyed wool fabrics were only little different using stannous chloride as mordant during three mordanting methods. Wool dyed without mordant showed yellowish-brown shade. The samples mordanted with copper sulfate, stannous chloride, and alum produced medium to dark grayish-brown, bright yellow and pale yellow shades, respectively. With ferrous sulfate, the colour was darker and duller. This may be associated with a change of ferrous sulfate into a ferric form by reacting with oxygen in the air. Ferrous and ferric forms coexisted on the fibers and their spectra overlapped, resulting in a shift of λmax and consequent colour change to a darker shad (Hwang, 2008). Additional, the tannins combined with ferrous salts to form complexes, which also result in a darker shade of fabric (Vankar, 2007). From the results, it can be postulated that wool fabric can be successfully dyed with eucalyptus leaf extract. This may be attributed to the fact that eucalyptus leaves are rich tannin (Conde et al., 1997), which are phenolic compounds that can form hydrogen bonds with carboxyl groups in the protein fibers (Agarwal & Patel, 2001).


Note: 1 20g/l dye concentration

Table 2. Colour value of wool fabric dyed with eucalyptus leaf extract by simultaneous mordanting and padding techniques, with using 10 g/l of metal mordants at different concentration of the dye

Alum and ferrous sulfate were the best mordant during simultaneous mordanting method of dyeing. However, copper sulfate showed the best mordant during simultaneous mordanting and pre-mordanting method of dyeing. For the *K/S* value on dyed wool fabrics were only little different using stannous chloride as mordant during three mordanting methods. Wool dyed without mordant showed yellowish-brown shade. The samples mordanted with copper sulfate, stannous chloride, and alum produced medium to dark grayish-brown, bright yellow and pale yellow shades, respectively. With ferrous sulfate, the colour was darker and duller. This may be associated with a change of ferrous sulfate into a ferric form by reacting with oxygen in the air. Ferrous and ferric forms coexisted on the fibers and their spectra overlapped, resulting in a shift of λmax and consequent colour change to a darker shad (Hwang, 2008). Additional, the tannins combined with ferrous salts to form complexes, which also result in a darker shade of fabric (Vankar, 2007). From the results, it can be postulated that wool fabric can be successfully dyed with eucalyptus leaf extract. This may be attributed to the fact that eucalyptus leaves are rich tannin (Conde et al., 1997), which are phenolic compounds that can form hydrogen bonds with carboxyl groups in the

Pad-batch on wool fabric Pad-dry on wool fabric

sample *K/S L\* a\* b\** 

1Dyed sample

1Dyed

5 1.50 76.1 3.5 14.2 1.13 77.7 3.5 12.0 10 1.60 76.0 3.5 15.0 1.54 76.3 3.6 14.1

20 1.86 75.4 3.5 15.8 1.86 75.9 3.4 15.8

5 1.65 78.2 0.4 23.6 1.65 79.4 0.1 27.2 10 1.91 76.8 0.1 24.0 1.81 78.0 0.1 27.6

20 2.55 74.9 0.7 22.9 2.60 74.5 1.0 27.2

5 3.27 63.8 0.04 21.1 2.32 65.5 2.0 19.6 10 3.44 62.6 1.0 21.2 2.62 64.0 2.8 19.5

20 4.12 59.6 2.2 21.1 2.80 62.5 3.3 19.0

5 3.93 40.1 1.3 -1.3 4.54 40.6 1.3 -1.0 10 4.23 40.0 1.1 -0.9 4.81 37.1 1.3 -1.0

20 4.62 38.5 1.2 -1.1 5.14 37.2 1.0 -0.9

5 2.15 83.8 -0.2 28.5 1.58 84.7 -0.9 22.5 10 2.38 84.1 -0.7 28.3 2.01 83.5 -0.4 27.4

20 2.67 83.4 -0.8 30.4 2.92 81.5 0.4 30.4

Table 2. Colour value of wool fabric dyed with eucalyptus leaf extract by simultaneous mordanting and padding techniques, with using 10 g/l of metal mordants at different

protein fibers (Agarwal & Patel, 2001).

*K/S L\* a\* b\** 

Dye Conc. (g/l)

Type of mordant

Without mordant

AlK(SO4)2 (Al)

> CuSO4 (Cu)

FeSO4 (Fe)

SnCl2 (Sn)

Note: 1 20g/l dye concentration

concentration of the dye


Note: 1 20g/l dye concentration

Table 3. Colour value of wool fabric dyed with eucalyptus leaf extract by post-mordanting and padding techniques, with using 10 g/l of metal mordants at different concentration of the dye

#### **6.3 Effect of quantity of mordant concentrations, time/ temperature on pad-dry and batching time on pad-batch**

Table 4 shows the colour values of wool fabric dyed with eucalyptus leaf extract by varying quantity of mordant concentrations. All measured sample showed the greatest λmax value at 400 nm. It can be seen that the *K/S* values increase with an increase of mordant concentration. The dyed uptake values were greater at the higher mordant concentration. This could be attributed to the darkening and dulling of shades due to mordant effect. Little different between the two padding techniques utilized for the study is observed. Wool fabric dyed with eucalyptus leaf extract in the absence mordant showed yellowish brown shades. Comparison of four metal mordants showed that the ferrous sulfate metal mordant gave the highest depth of shade on wool fabric. Thus ferrous sulfate was the best mordant during mordanting method of dyeing. This could be attributed to difference in CIELAB values of the dyed samples. The mordant activity of the five sequences was as follows: Fe > Cu > Al > Sn > without mordanted in wool fabric, the absorption of colour by wool fabric was enhanced by using metal mordants.

Natural Dye from Eucalyptus Leaves and

sulfate by using simultaneous mordanting

using simultaneous mordanting

**by simultaneous pad-dyeing** 

Application for Wool Fabric Dyeing by Using Padding Techniques 69

wool fabric on drying at 90°C for 5 minutes. The pad-batch dyeing process was carried out at room temperature with batching times of different lengths to assure an operation as economic as possible. Fig. 5 shows that low colour strength required a period of 1 hour, medium colour strength of 6-12 hours and high colour strength a period of 24 hours. The colour strength obtained was increased as the batching time increased for wool fabrics.

Fig. 4. Effect of drying time and temperature of pad-dry technique on the colour strength (*K/S* values) of wool fabric dyed with 20 g/l eucalyptus leaf extract and using 20 g/l ferrous

Fig. 5. Effect of batching time of pad-batch technique on the colour strength (*K/S* values) of wool fabric dyed with 20 g/l eucalyptus leaf extract and using 20 g/l ferrous sulfate by

**6.4 The percentage yield (exploitation) of wool fabric dyed with eucalyptus leaf extract** 

It was estimated that the best shades (deep and colour fastness) are obtained when mordanting with ferrous sulfate (FeSO4·7H2O) and, therefore, this mordant was used for the experiments. The following concentration range of eucalyptus leaf extract and mordant FeSO4·7H2O in the same concentration was used: 1, 5, 10, 20, 30, and 40 g/l, and in all cases anionic wetting agent in the concentration of 1 g/l was added to the padding bath. Glacial


Note: 1 20g/l metal mordants concentration

Table 4. Colour value of wool fabric dyed with eucalyptus leaf extract by simultaneous mordanting and padding techniques, with using 20 g/l of dye concentration at different concentration of the mordant

From the results, it is clear that ferrous sulfate and copper sulfate mordants are well known for their ability to form coordinate complexes and in this experiment both readily chelated with the dye. As the coordination numbers of ferrous sulfate and copper sulfate are 6 and 4 respectively, some co-ordination sites remained unoccupied when they interacted with the fiber. Functional groups such as amino and carboxylic acid groups on the fiber can occupy these sites. Thus this metal can form a ternary complex on one site with the fiber and on the other site with the dye (Bhattacharya & Shah, 2000). Stannous chloride and alum metals formed weak coordination complexes with the dye, they tend to form quite strong bonds with the dye but not with the fiber, so they block the dye and reduce the dye interaction with the fiber (Bhattacharya & Shah, 2000).

The effect of time and temperature on colour strength (*K/S)* value was evaluated by padding a sample of wool fabric with eucalyptus leaf extract and ferrous sulfate as mordant. The samples were processed only by drying condition were 40°C, 60°C and 90°C for 1, 3, 5 and 10 minutes. The *K/S* values obtained are shown in Fig. 4. It is clear that the colour strength (*K/S*) values increase with in crease in the drying time and temperature in wool fabric. A study of Fig. 4 reveals that the high colour strength values (ca. 7.60) was achieved for the

5 2.18 76.2 0.5 28.2 2.09 77.8 0.8 28.0 10 2.55 74.9 0.7 29.9 2.60 74.5 1.0 29.1

20 3.91 72.8 1.0 32.1 3.97 72.0 1.2 31.6

5 3.84 61.3 2.4 20.9 3.80 62.4 2.3 20.2 10 4.12 59.6 2.7 21.1 4.08 60.0 3.3 19.0

20 5.00 54.4 2.8 23.1 4.87 55.7 3.2 20.1

5 4.81 40.0 1.0 -0.9 4.95 39.1 1.1 -0.6 10 4.98 38.5 1.2 -1.1 5.14 37.0 1.0 -0.9

20 7.28 36.9 0.7 -1.4 7.60 36.0 0.9 -0.7

5 2.64 83.3 -1.6 32.2 2.66 83.1 -2.3 31.8 10 2.67 83.4 -1.2 30.4 2.71 82.5 -2.4 30.4

20 3.11 81.8 -2.1 35.3 3.13 81.4 -2.7 34.6

From the results, it is clear that ferrous sulfate and copper sulfate mordants are well known for their ability to form coordinate complexes and in this experiment both readily chelated with the dye. As the coordination numbers of ferrous sulfate and copper sulfate are 6 and 4 respectively, some co-ordination sites remained unoccupied when they interacted with the fiber. Functional groups such as amino and carboxylic acid groups on the fiber can occupy these sites. Thus this metal can form a ternary complex on one site with the fiber and on the other site with the dye (Bhattacharya & Shah, 2000). Stannous chloride and alum metals formed weak coordination complexes with the dye, they tend to form quite strong bonds with the dye but not with the fiber, so they block the dye and reduce the dye interaction

The effect of time and temperature on colour strength (*K/S)* value was evaluated by padding a sample of wool fabric with eucalyptus leaf extract and ferrous sulfate as mordant. The samples were processed only by drying condition were 40°C, 60°C and 90°C for 1, 3, 5 and 10 minutes. The *K/S* values obtained are shown in Fig. 4. It is clear that the colour strength (*K/S*) values increase with in crease in the drying time and temperature in wool fabric. A study of Fig. 4 reveals that the high colour strength values (ca. 7.60) was achieved for the

Table 4. Colour value of wool fabric dyed with eucalyptus leaf extract by simultaneous mordanting and padding techniques, with using 20 g/l of dye concentration at different

mordant - 1.86 75.4 3.5 15.8 1.86 75.9 3.4 15.8

1Dyed

Pad-batch on wool fabric Pad-dry on wool fabric

sample *K/S L\* a\* b\** 

1Dyed sample

Type of mordant

Without

AlK(SO4)2 (Al)

> CuSO4 (Cu)

FeSO4 (Fe)

SnCl2 (Sn)

Note: 1 20g/l metal mordants concentration

with the fiber (Bhattacharya & Shah, 2000).

concentration of the mordant

Conc. (g/l)

*K/S L\* a\* b\** 

wool fabric on drying at 90°C for 5 minutes. The pad-batch dyeing process was carried out at room temperature with batching times of different lengths to assure an operation as economic as possible. Fig. 5 shows that low colour strength required a period of 1 hour, medium colour strength of 6-12 hours and high colour strength a period of 24 hours. The colour strength obtained was increased as the batching time increased for wool fabrics.

Fig. 4. Effect of drying time and temperature of pad-dry technique on the colour strength (*K/S* values) of wool fabric dyed with 20 g/l eucalyptus leaf extract and using 20 g/l ferrous sulfate by using simultaneous mordanting

Fig. 5. Effect of batching time of pad-batch technique on the colour strength (*K/S* values) of wool fabric dyed with 20 g/l eucalyptus leaf extract and using 20 g/l ferrous sulfate by using simultaneous mordanting

#### **6.4 The percentage yield (exploitation) of wool fabric dyed with eucalyptus leaf extract by simultaneous pad-dyeing**

It was estimated that the best shades (deep and colour fastness) are obtained when mordanting with ferrous sulfate (FeSO4·7H2O) and, therefore, this mordant was used for the experiments. The following concentration range of eucalyptus leaf extract and mordant FeSO4·7H2O in the same concentration was used: 1, 5, 10, 20, 30, and 40 g/l, and in all cases anionic wetting agent in the concentration of 1 g/l was added to the padding bath. Glacial

Natural Dye from Eucalyptus Leaves and

Percentage of pick up

*C0* (g/l)

mordant of wool fabric

(Gies et al., 2000)

process was used in this study.

Application for Wool Fabric Dyeing by Using Padding Techniques 71

1 80 0.8 0.5 68.0 1.8 5 80 4 2.5 62.8 2.8 10 80 8 4.2 53.2 3.7 20 80 16 8.3 52.0 3.9 30 80 24 12.6 52.6 4.0 40 80 32 16.0 52.2 4.5 Table 5. Percentage yield and *K/S* values obtained by the simultaneous pad-dyeing/

**6.5 UV protection properties of wool fabric dyed with eucalyptus leaf extract** 

The transmittance and UPF values of the original wool fabric, and fabrics dyed with the eucalyptus leaf extract were measured using Shimadzu UV3101 PC (UV-VIS-NIR Scanning Spectrophotometer) in the range of 190 nm to 2100 nm. The UPF value of the fabric was determined from the total spectral transmittance based on AS/NZ 4399:1996 as follows

> 400 ∑ Eλ S<sup>λ</sup> Δλ 290 400

where *Eλ* is the relative erythemal spectral effectiveness (unitless), *Sλ* is the solar ultraviolet radiation (UVR) spectral irradiance in W.m-2.nm-1, *Tλ* is the measured spectral transmission of the fabric, *Δλ* is the bandwidth in millimeter, and *λ* is the wavelength in nanometre. The UVR band consists of three regions: UV-A band (320 nm to - 400 nm), UV-B band (290 nm to 320 nm), and UV-C band (200 nm to 290 nm) (Feng et al., 2007). The highest energy region, the UV-C band, is absorbed completely by oxygen and ozone in the upper atmosphere. Of the solar UV radiation reaching the earth's surface, 6% is in the UV-B region and 94% in the UV-A region (Allen & Bain, 1994). UV-A causes little visible reaction on the skin but has been shown to decrease the immunological response of skin cells (Sarkar, 2003). UV-B is the most responsible for the development of skin cancers (Sarkar, 2003). Therefore, the transmittance of UVR, including UV-A and UV-B, through the fabrics was evaluated in this experiment. Fabrics with a UPF value in the range of 15-24 are defined as providing "good UV protection", 25-39 as "very Good UV protection", and 40 or greater as "excellent UV protection" (Sarkar, 2003). There is no rating assigned if the UPF value is greater than 50. A commercially produced plain-weave wool fabric (thickness 0.36 mm, weight 193 g/m2, fabric count per inch 62 x 54) was used in this experimental. The thread count, fabric thickness, and fabric weight characteristics of the wool fabric was in accordance with ASTM D3775-98, ISO 5084-1996, and ISO 3801-1997, respectively. A pre-mordanting padding

290

UPF =

∑ Eλ Sλ TλΔλ

To investigate the UV-protection property of eucalyptus leaves dye, UV transmittance spectra of the wool fabric with or without dyeing and the dyed wool fabric with mordants were

*Cs* (mg/g) Yield (%)

*K/S* value (400 nm)

*Cpi* (mg/g)

acetic acid was added to maintain the pH of the liquid at 4. The simultaneous padding was carried out at room temperature in a two-bowl padding mangle using 80% pick up. After padding (2 seconds), the samples were dried at 90ºC for 5 minutes and after 1 hour, all samples were repeatedly rinsed in warm water at 60ºC until the rinsing water remained colourless. The rinsed water was collected with the rest of dyeing bath in the volumetric flask and filled up to the defined volume for absorbance measurement by UV–vis spectrophotometer (at the wavelength of 270 nm at which the maximum absorbance was recorded). The concentration of eucalyptus leaf extract fixed in the fiber and percentage of its use (percentage of yield) from bath on fiber were calculated from the absorbance of the rinsing water by using the standard graph. Relationship between bath concentration and padding condition were calculated from Eq. (1) to Eq. (6) (Mongkholrattanasit et al., 2009). We assume when the initial dye concentration in the pad bath is *C0* (g/l). The quantity of dye transported by fabric is *Cpi* (mg/g)

$$\mathbf{C}\_{pi} = \frac{\% \text{ pickup}}{100} \cdot \mathbf{C}\_0 \tag{1}$$

The concentration of dye in conjoined-water after rinsing can be expressed as:

$$\mathbf{C}\_r = \frac{Absorbance}{\mathbf{c} \cdot \mathbf{l}} \tag{2}$$

where *Cr* = the concentration of dye in conjoined-water (mg/l), *ε* = absorption coefficient (l/mole.cm) and *l* = layer of solution (cm). Then the concentration of dye, which was stripped from material, is *Cw* (mg/g)

$$C\_w = \frac{C\_r}{1,000} \frac{V}{g} \tag{3}$$

where *V* = total volume after rinsing (ml) and *g* = weight of material (g). The concentration of dye absorbed on material, *Cs* (mg/g) was calculated as:

$$\mathbf{C}\_s = \mathbf{C}\_{pi} - \mathbf{C}\_w \tag{4}$$

The percentage of dye which stripped from the material can be shown as Eq. (5)

$$\mathcal{W} = \frac{\mathbb{C}\_w \cdot 100}{\mathbb{C}\_{pi}} \tag{5}$$

where *W* = the percentage of dye which stripped from the material (%). And the percentage of exploitation of dye (yield), *E* (%) can be calculated as:

$$E = 100 - \text{W} \tag{6}$$

Wool fabric dyed with the water extract of eucalyptus leaves in the presence of the FeSO4 mordant in the same padding bath shows a colour range of a brown grey shade to a dark grey shade. In Table 5, the results are presented. The yield (exploitation) of the colouring component of eucalyptus leaf extract in wool fabric is about 68%–52% from the lowest to the highest concentrations, and this corresponds to the medium deep brown-grey shades in the concentrations of more than 20 g/l eucalyptus leaf extract.

acetic acid was added to maintain the pH of the liquid at 4. The simultaneous padding was carried out at room temperature in a two-bowl padding mangle using 80% pick up. After padding (2 seconds), the samples were dried at 90ºC for 5 minutes and after 1 hour, all samples were repeatedly rinsed in warm water at 60ºC until the rinsing water remained colourless. The rinsed water was collected with the rest of dyeing bath in the volumetric flask and filled up to the defined volume for absorbance measurement by UV–vis spectrophotometer (at the wavelength of 270 nm at which the maximum absorbance was recorded). The concentration of eucalyptus leaf extract fixed in the fiber and percentage of its use (percentage of yield) from bath on fiber were calculated from the absorbance of the rinsing water by using the standard graph. Relationship between bath concentration and padding condition were calculated from Eq. (1) to Eq. (6) (Mongkholrattanasit et al., 2009). We assume when the initial dye concentration in the pad bath is *C0* (g/l). The quantity of

> % 100 *pi*

*Absorbance <sup>C</sup>* 

where *Cr* = the concentration of dye in conjoined-water (mg/l), *ε* = absorption coefficient (l/mole.cm) and *l* = layer of solution (cm). Then the concentration of dye, which was

> 1,000 *<sup>r</sup> <sup>w</sup> <sup>C</sup> <sup>V</sup> <sup>C</sup>*

> > 100 *<sup>w</sup> pi*

*C*

where *W* = the percentage of dye which stripped from the material (%). And the percentage

 *E* = 100 – *W* (6) Wool fabric dyed with the water extract of eucalyptus leaves in the presence of the FeSO4 mordant in the same padding bath shows a colour range of a brown grey shade to a dark grey shade. In Table 5, the results are presented. The yield (exploitation) of the colouring component of eucalyptus leaf extract in wool fabric is about 68%–52% from the lowest to the highest concentrations, and this corresponds to the medium deep brown-grey shades in

where *V* = total volume after rinsing (ml) and *g* = weight of material (g). The concentration

The concentration of dye in conjoined-water after rinsing can be expressed as:

*r*

The percentage of dye which stripped from the material can be shown as Eq. (5)

*<sup>C</sup> <sup>W</sup>*

0

*pick up C C* (1)

*<sup>l</sup>* (2)

*<sup>g</sup>* (3)

*CC C <sup>s</sup> pi w* (4)

(5)

dye transported by fabric is *Cpi* (mg/g)

stripped from material, is *Cw* (mg/g)

of dye absorbed on material, *Cs* (mg/g) was calculated as:

of exploitation of dye (yield), *E* (%) can be calculated as:

the concentrations of more than 20 g/l eucalyptus leaf extract.


Table 5. Percentage yield and *K/S* values obtained by the simultaneous pad-dyeing/ mordant of wool fabric

#### **6.5 UV protection properties of wool fabric dyed with eucalyptus leaf extract**

The transmittance and UPF values of the original wool fabric, and fabrics dyed with the eucalyptus leaf extract were measured using Shimadzu UV3101 PC (UV-VIS-NIR Scanning Spectrophotometer) in the range of 190 nm to 2100 nm. The UPF value of the fabric was determined from the total spectral transmittance based on AS/NZ 4399:1996 as follows (Gies et al., 2000)

$$\begin{array}{rcl} 400 & & \\ & \sum\_{\lambda} \mathbf{E}\_{\lambda} \mathbf{S}\_{\lambda} \,\Delta\_{\lambda} \\ & 290 & \\ \text{UPF} & = & \overline{400} \\ & \sum\_{\lambda} \mathbf{E}\_{\lambda} \mathbf{S}\_{\lambda} \,\mathbf{T}\_{\lambda} \,\Delta\_{\lambda} \\ & 290 & \end{array}$$

where *Eλ* is the relative erythemal spectral effectiveness (unitless), *Sλ* is the solar ultraviolet radiation (UVR) spectral irradiance in W.m-2.nm-1, *Tλ* is the measured spectral transmission of the fabric, *Δλ* is the bandwidth in millimeter, and *λ* is the wavelength in nanometre. The UVR band consists of three regions: UV-A band (320 nm to - 400 nm), UV-B band (290 nm to 320 nm), and UV-C band (200 nm to 290 nm) (Feng et al., 2007). The highest energy region, the UV-C band, is absorbed completely by oxygen and ozone in the upper atmosphere. Of the solar UV radiation reaching the earth's surface, 6% is in the UV-B region and 94% in the UV-A region (Allen & Bain, 1994). UV-A causes little visible reaction on the skin but has been shown to decrease the immunological response of skin cells (Sarkar, 2003). UV-B is the most responsible for the development of skin cancers (Sarkar, 2003). Therefore, the transmittance of UVR, including UV-A and UV-B, through the fabrics was evaluated in this experiment. Fabrics with a UPF value in the range of 15-24 are defined as providing "good UV protection", 25-39 as "very Good UV protection", and 40 or greater as "excellent UV protection" (Sarkar, 2003). There is no rating assigned if the UPF value is greater than 50. A commercially produced plain-weave wool fabric (thickness 0.36 mm, weight 193 g/m2,

fabric count per inch 62 x 54) was used in this experimental. The thread count, fabric thickness, and fabric weight characteristics of the wool fabric was in accordance with ASTM D3775-98, ISO 5084-1996, and ISO 3801-1997, respectively. A pre-mordanting padding process was used in this study.

To investigate the UV-protection property of eucalyptus leaves dye, UV transmittance spectra of the wool fabric with or without dyeing and the dyed wool fabric with mordants were

Natural Dye from Eucalyptus Leaves and

good UV protection (UPF values between 25 and 39).

Dye Conc. (g/l)

less UV radiation.

Mordant

Application for Wool Fabric Dyeing by Using Padding Techniques 73

For the samples mordanted with AlK(SO4)2 , CuSO4, FeSO4 and SnCl2, the percent UV-B transmittance was in the range of 0.8-1.9 %, 1.0-1.6%, 0.7-1.1%, and 1.2-2.7%, respectively for pad-batch and 0.7-1.8 %, 0.9-1.7%, 0.7-1.4%, and 1.2-2.5%, respectively for pad-dry. It is clearly seen that the values of the spectral transmittance are decreased with the mordants such as AlK(SO4)2, CuSO4, FeSO4, and SnCl2 and different mordants had different effects on the spectral transmittance of the fabric dyed (Feng et al., 2007). Additionally, the colour and colour depth of the fabric can be related to UV transmittance in which light colours transmit more UV radiation than dark colours (Wilson et al., 2008). Table 6 shows the UPF values and protection class of wool fabric dyed by eucalyptus leaves with and without metal mordants by pad-dry and pad-batch dyeing techniques. Little difference is observed between the two padding techniques utilized for this study. The undyed fabric had a high transmittance and a very low UPF value of 10.8. The dyed samples without metal mordant in both dyeing techniques show UPF values between 32.8 and 35.4, which can be rated as offering Very

From the transmission data and the corresponding UPF values, all metal mordants used in this study caused a reduction in UV radiation transmission through the wool fabric. Wool fabric dyed by the metal mordants at 5 g/l concentrations of dye in the pad-dry and the pad-batch dyeing techniques could be classified as offering Excellent UV protection (UPF values 40 or greater). Wool fabrics, which after dyeing with and without mordant are rated as very good to excellent UV protection because wool fabric have low porosity and high weight and thickness. Therefore, wool fabric gives high UPF and permitting transmission of


Without 5 32.8 Very good 35.4 Very good

AlK(SO4)2 5 59.0 Excellent 55.1 Excellent

CuSO4 5 67.9 Excellent 65.0 Excellent

FeSO4 5 85.3 Excellent 81.8 Excellent

SnCl2 5 46.9 Excellent 45.5 Excellent

The colour fastness to washing, light, perspiration, water and rubbing of the dyed samples was determined according to ISO 105-C06 A1S:1994, ISO 105-B02:1994, ISO 105 E04: 1994,

Table 6. UPF values, protection class, and *K/S* values of wool fabric dyed with 5 g/l

eucalyptus leaf extract dye solution and using 10 g/l mordants

**6.6 Effect of dyeing technique on fastness properties** 

ISO 105-E01: 1994 and ISO 105-X12:2001, respectively.

Pad-batch Pad-dry UPF UPF Protection class UPF UPF Protection class

compared. The percent UV transmittance data of wool fabric dyed with and without a mordanting agent are shown in Fig. 6. The results show significantly different between the dyed and undyed fabrics, which yields a high UV transmittance. The UV transmittance of the undyed wool was in the range of about 4-12% in the UV-B band and about 12-37% in the UV-A band. This indicates that the resistance of undyed fabrics to ultraviolet ray was very poor. While the UV transmittance of wool fabrics dyed by eucalyptus leaf extract appeared to be lower than 5% in the UV-B region. Generally, the UV protection property of fabrics is evaluated as good when the UV transmittance is less than 5% (Feng et al., 2007 ; Teng & Yu, 2003).

Note: Al = AlK(SO4)2 , Cu = CuSO4, Fe = FeSO4 , Sn = SnCl2

Fig. 6. UV transmission of wool fabric dyed with 5 g/l eucalyptus leaf extract dye solution, , using 10 g/l mordants by (a) pad-batch and (b) pad-dry techniques.

compared. The percent UV transmittance data of wool fabric dyed with and without a mordanting agent are shown in Fig. 6. The results show significantly different between the dyed and undyed fabrics, which yields a high UV transmittance. The UV transmittance of the undyed wool was in the range of about 4-12% in the UV-B band and about 12-37% in the UV-A band. This indicates that the resistance of undyed fabrics to ultraviolet ray was very poor. While the UV transmittance of wool fabrics dyed by eucalyptus leaf extract appeared to be lower than 5% in the UV-B region. Generally, the UV protection property of fabrics is evaluated as good when the UV

> **Undyed Eucalyptus Eucalyptus + Al Eucalyptus + Cu Eucalyptus + Fe Eucalyptus + Sn**

**290 300 310 320 330 340 350 360 370 380 390 400 Wavelength (nm)**

**290 300 310 320 330 340 350 360 370 380 390 400 Wavelength (nm)**

Fig. 6. UV transmission of wool fabric dyed with 5 g/l eucalyptus leaf extract dye solution, ,

transmittance is less than 5% (Feng et al., 2007 ; Teng & Yu, 2003).

Note: Al = AlK(SO4)2 , Cu = CuSO4, Fe = FeSO4 , Sn = SnCl2

using 10 g/l mordants by (a) pad-batch and (b) pad-dry techniques.

**Transmittance (%)**

(b)

**Transmittance (%)**

(a)

For the samples mordanted with AlK(SO4)2 , CuSO4, FeSO4 and SnCl2, the percent UV-B transmittance was in the range of 0.8-1.9 %, 1.0-1.6%, 0.7-1.1%, and 1.2-2.7%, respectively for pad-batch and 0.7-1.8 %, 0.9-1.7%, 0.7-1.4%, and 1.2-2.5%, respectively for pad-dry. It is clearly seen that the values of the spectral transmittance are decreased with the mordants such as AlK(SO4)2, CuSO4, FeSO4, and SnCl2 and different mordants had different effects on the spectral transmittance of the fabric dyed (Feng et al., 2007). Additionally, the colour and colour depth of the fabric can be related to UV transmittance in which light colours transmit more UV radiation than dark colours (Wilson et al., 2008). Table 6 shows the UPF values and protection class of wool fabric dyed by eucalyptus leaves with and without metal mordants by pad-dry and pad-batch dyeing techniques. Little difference is observed between the two padding techniques utilized for this study. The undyed fabric had a high transmittance and a very low UPF value of 10.8. The dyed samples without metal mordant in both dyeing techniques show UPF values between 32.8 and 35.4, which can be rated as offering Very good UV protection (UPF values between 25 and 39).

From the transmission data and the corresponding UPF values, all metal mordants used in this study caused a reduction in UV radiation transmission through the wool fabric. Wool fabric dyed by the metal mordants at 5 g/l concentrations of dye in the pad-dry and the pad-batch dyeing techniques could be classified as offering Excellent UV protection (UPF values 40 or greater). Wool fabrics, which after dyeing with and without mordant are rated as very good to excellent UV protection because wool fabric have low porosity and high weight and thickness. Therefore, wool fabric gives high UPF and permitting transmission of less UV radiation.


Table 6. UPF values, protection class, and *K/S* values of wool fabric dyed with 5 g/l eucalyptus leaf extract dye solution and using 10 g/l mordants

#### **6.6 Effect of dyeing technique on fastness properties**

The colour fastness to washing, light, perspiration, water and rubbing of the dyed samples was determined according to ISO 105-C06 A1S:1994, ISO 105-B02:1994, ISO 105 E04: 1994, ISO 105-E01: 1994 and ISO 105-X12:2001, respectively.

Natural Dye from Eucalyptus Leaves and

Table 9. Colour fastness to rubbing (ISO 105-X12: 2001).

Note: Al = AlK(SO4)2, Cu = CuSO4, Fe = FeSO4, Sn = SnCl2 Table 10. Colour fastness to water (ISO 105-E01: 1994)

Note: Al = AlK(SO4)2, Cu = CuSO4, Fe = FeSO4, Sn = SnCl2

Table 11. Colour fastness to perspiration (ISO 105-E04: 1994)

mordant

Acid

Alkaline

Application for Wool Fabric Dyeing by Using Padding Techniques 75

without 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5 AlK(SO4)2 4-5 4-5 4 4-5 4-5 4-5 4-5 4-5 CuSO4 4-5 4-5 4 4-5 4-5 4 4-5 4 FeSO4 4 4 4 3-4 4 3-4 4 3-4 SnCl2 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5

Fastness Pad-batch Pad-dry

Colour staining

Fastness Pad-batch Pad-dry

Colour staining

Colour change 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5

Colour change 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5


Colour staining


Colour change 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5


Colour staining Pad-batch Pad-dry Warp direction Weft direction Warp direction Weft direction Dry Wet Dry Wet Dry Wet Dry Wet

Without Al Cu Fe Sn Without Al Cu Fe Sn

Without Al Cu Fe Sn Without Al Cu Fe Sn

The fastness rating of wool fabric dyed with or without mordants at 20 g/l dye concentration is presented in Tables 7 through 11. When comparing the fastness rating of the samples dyed using the two padding techniques, it can be postulated that the pad-batch technique gives nearly the same fastness properties as the pad-dry technique. Table 7 indicates that the washing fastness ratings of wool fabric dyed with eucalyptus leaves were very good (4-5). However, the light fastness was only fair (3-4), as shown in Table 8. The colour fastness to rubbing is shown to be in range of 4 to 4-5 (good to very good), except for fabrics mordanted with FeSO4, whose rating was only 3-4 (fair to good) when subjected to wet rubbing, as shown in Table 9. The rating obtained for colour fastness to water in term of the degree of colour change and colour staining were very good (4 to 4-5), as shown in Table 10. The colour fastness to perspiration in acid and alkaline solution of fabrics dyed with and without metal mordants are shown in range of 4 to 4-5 as seen in Tables 11. The good fastness properties of wool fabric dyed with eucalyptus leaf extract may be attributed to the fact that these dyes contain tannin, which may help covalent bond formation with the fiber, thereby resulting in good fixation on the fibrous material. Again, these tannins, having a phenolic structure, can form metal chelation with different mordants. Hence, after mordanting, these tannins are insoluble in water, ultimately improving washing, water, and perspiration fastness (Agarwal & Patel, 2001).


Note: Al = AlK(SO4)2, Cu = CuSO4, Fe = FeSO4, Sn = SnCl2

Table 7. Colour fastness to washing at 40ºC (ISO 105-C06 A1S: 1994)


Note: Al = AlK(SO4)2, Cu = CuSO4, Fe = FeSO4, Sn = SnCl2

Table 8. Colour fastness to light (ISO 105-B02: 1994).

The fastness rating of wool fabric dyed with or without mordants at 20 g/l dye concentration is presented in Tables 7 through 11. When comparing the fastness rating of the samples dyed using the two padding techniques, it can be postulated that the pad-batch technique gives nearly the same fastness properties as the pad-dry technique. Table 7 indicates that the washing fastness ratings of wool fabric dyed with eucalyptus leaves were very good (4-5). However, the light fastness was only fair (3-4), as shown in Table 8. The colour fastness to rubbing is shown to be in range of 4 to 4-5 (good to very good), except for fabrics mordanted with FeSO4, whose rating was only 3-4 (fair to good) when subjected to wet rubbing, as shown in Table 9. The rating obtained for colour fastness to water in term of the degree of colour change and colour staining were very good (4 to 4-5), as shown in Table 10. The colour fastness to perspiration in acid and alkaline solution of fabrics dyed with and without metal mordants are shown in range of 4 to 4-5 as seen in Tables 11. The good fastness properties of wool fabric dyed with eucalyptus leaf extract may be attributed to the fact that these dyes contain tannin, which may help covalent bond formation with the fiber, thereby resulting in good fixation on the fibrous material. Again, these tannins, having a phenolic structure, can form metal chelation with different mordants. Hence, after mordanting, these tannins are insoluble in water, ultimately improving washing, water, and

Pad-batch Pad-dry

Without

Pad-dry (Colour change)

Al Cu Fe Sn

Al Cu Fe Sn

Colour change 4 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5 4-5


Without Al Cu Fe Sn Without Al Cu Fe Sn 3 3 3-4 4 3 3 3 3-4 3-4 3

perspiration fastness (Agarwal & Patel, 2001).

Without

Note: Al = AlK(SO4)2, Cu = CuSO4, Fe = FeSO4, Sn = SnCl2

Note: Al = AlK(SO4)2, Cu = CuSO4, Fe = FeSO4, Sn = SnCl2 Table 8. Colour fastness to light (ISO 105-B02: 1994).

Table 7. Colour fastness to washing at 40ºC (ISO 105-C06 A1S: 1994)

Pad-batch (Colour change)

Fastness

Colour staining


Table 9. Colour fastness to rubbing (ISO 105-X12: 2001).


Note: Al = AlK(SO4)2, Cu = CuSO4, Fe = FeSO4, Sn = SnCl2



Note: Al = AlK(SO4)2, Cu = CuSO4, Fe = FeSO4, Sn = SnCl2

Table 11. Colour fastness to perspiration (ISO 105-E04: 1994)

Natural Dye from Eucalyptus Leaves and

eucalyptus leave.

**10. References** 

Application for Wool Fabric Dyeing by Using Padding Techniques 77

was observed that the ultraviolet (UV) protection factor (UPF) values rated as excellent for the wool fabric. In addition, a darker colour, such as that provided by a ferrous sulfate

The application of eucalyptus leaves dye on wool fabrics by pad-batch and pad-dry technique of dyeing can be considered as an affective eco-option because it gives extremely good results with substantial minimization of processing cost. In case of pad-dry technique, the average hot air consumption is considerably high whereas no hot air is being consumed in cold pad-batch process which leads to energy conservation. However, the time employed for the fixation of eucalyptus leaves dye is very long in cold pad-batch technique. So, these techniques can be considered as best suitable for small scale industries or cottage dyeing of

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Industrial Research, ISBN 81-89579-01-0 ,New Delhi, India

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Vankar, P. S. (2007). *Handbook on natural dyes for industrial applications*, National Institute of

Glover, B. & Pierce, J. H. (1993). Are natural colorants good for your health*? Journal of the Society of Dyers and Colourists*, Vol. 109, No. 1, pp. 5-7, ISSN 0037-9859 Hwang, E. K. ; Lee, Y. H. & Kim, H. D. (2008). Dyeing, fastness, and deodorizing properties of

Flint, I. (2007). An antipodean alchemy–The eucalypt dyes. *Turkey Red Journal*, Vol. 13, No. 1, (Fall 2007). Available from : http://www.turkeyredjournal.com/archives/V13\_I1/flint.html Ali, S. ; Nisar, N. & Hussain, T. (2007). Dyeing properties of natural dyes extracted from

Vankar, P. S. ; Tiwari, V. & Srivastava, J. (2006). Extracts of steam bark of *Eucalyptus Globules*

*Agricultural and Food Chemistry*, Vol. 5, No. 6, pp. 1664-1669, ISSN 1579-4377 Chapuis-Lardy, L. ; Contour-Ansel, D. & Bernhard-Reversat, F. (2002). High performance liquid

(Congo). *Plant Science – Kidlington*, Vol. 163, No. 2, pp. 217-222, ISSN 0168-9452 Conde, E.; Cadahia, E. & Garcia-Vallejo, M. C. (1997). Low molecular weight polyphenols in

Conde, E.; Cadahia, E.; Garcia-Vallejo, M. C. & Fernandez de Simon, B. (1997). High

glycosides. *Phytochemical Analysis*, Vol. 8*,* No*.* 2, pp. 78-83, ISSN 0958-0344 Mongkholrattanasit, R. ; Wongphakdee, W. & Sirikasemlert, C. (2007). Dyeing and colour

*RMUTP Research Journal*, Vol. 1, No. 1, pp. 41-49, ISSN 1906-0432

cotton, silk, and wool fabrics dyed with gardenia, coffee sludge, *Cassia tora. L.*, and pomegranate extracts. *Fibers and Polymers*, Vol. 9, No. 3, pp. 334-340, ISSN 1857-0052 Hunger, K. (2003). *Industrial dyes: Chemistry, Properties, Applications*, WILEY-VCH Verlag

eucalyptus*. The Journal of The Textile Institute,* Vol. 98, No. 6, pp. 559-562, ISSN 1754-2340

as food dye with high antioxidant properties. *Electronic Journal of Environmental,* 

chromatography of water-soluble phenolics in leaf litter of three eucalyptus hybrids

leaves of *Eucalyptus camaldulensis. E. globules and E. rudis*. *Phytochemical Analysis*,

pressure liquid chromatographic analysis of polyphenols in leaves of *Eucalyptus cmadulensis*. *E. globules* and *E. rudis*: proanthocyanidins, ellagitannins and flavonol

fastness properties of silk and cotton fabrics dyed with eucalyptus bark extract.

mordant, gave better protection because of higher UV absorption.

0-470-51199-2, West Sussex, England

Vol. 8, No. 4, pp. 186-193, ISSN 0958-0344

### **7. Potential of eucalyptus leaves dye**

#### **7.1 Potential commercial applications**

Natural dyes cannot be used as simple alternatives to synthetic dyes and pigments. They do, however, have the potential for application, in specified areas, to reduce the consumption of some of the more highly polluting synthetic dyes. They also have the potential to replace some of the toxic, sensitizing and carcinogenic dyes and intermediates (Deo & Desai, 1999). Eucalyptus leaves, as natural dye, has greater potential because it is grown already on an industrial scale. It also shows good fastness on wool substrate.

#### **7.2 Potential effluent problems**

The effluent problems of synthetic dyes occur not only during their application in the textile industry, but also during their manufacture, and possibly during the synthesis of their intermediates and other raw materials. The application of synthetic dyes also requires metal salts for exhaustion, fixation, etc (Deo & Desai, 1999). Natural dyes, like eucalyptus leaves do not cause damage the environment by their extraction and many could be used satisfactorily without mordants, although it is true that the use of mordant improves the depth of shade for natural dyes. These mordants are normally metal salts and hence damage to the environment is still possible, albeit to a smaller extent than for synthetic dyes in textile applications. The research in this field has already identified a few "natural mordant", such as *Entada spiralis Ridl* (Chairat et al., 2007) and harda (*Chebulic myrabolan*) (Deo & Desai, 1999). The avoidance of metal-based mordants, or their replacement by natural mordants, may assist in the preservation of the environment.

#### **8. Acknowledgement**

The authors would like to thank Ing. Martina Viková from the Technical University of Liberec, Czech Republic, for testing of the UV transmission and UPF values.

#### **9. Conclusions**

A wool fabric dyed in a solution containing the eucalyptus leaf extract showed a shade of pale yellowish-brown. The exception was when the fabric was dyed with the ferrous sulfate mordant, resulting in a shade of dark greyish-brown. The yield (exploitation) of the coloring component of eucalyptus leaf extract is good in wool fabric (about 68%–52% from the lowest to the highest concentrations). It can be observed that the *K/S* values increase with an increase of dye concentration. Little difference between the two padding techniques utilized for the wool fabric dyes by three mordanting methods, except wool fabrics mordanted with copper sulfate whose gave a high *K/S* values on the pad-batch technique than pad-dry technique. In all cases ferrous sulfate mordant yielded the best dyeing results, and the next good result was obtained in the order of copper sulfate, stannous chloride and alum. As observed from the *K/S* values, in the case of wool fabrics dyed with alum by using postmordanting method gave lower colour strength than without mordant. Alum and ferrous sulfate were the best mordant during simultaneous mordanting method of dyeing. However, copper sulfate showed the best mordant during simultaneous mordanting and pre-mordanting method of dyeing. For the *K/S* value on dyed wool fabrics were only little different using stannous chloride as mordant during three mordanting methods. The fastness properties ranged from good to excellent, while light fastness was fair to good. It was observed that the ultraviolet (UV) protection factor (UPF) values rated as excellent for the wool fabric. In addition, a darker colour, such as that provided by a ferrous sulfate mordant, gave better protection because of higher UV absorption.

The application of eucalyptus leaves dye on wool fabrics by pad-batch and pad-dry technique of dyeing can be considered as an affective eco-option because it gives extremely good results with substantial minimization of processing cost. In case of pad-dry technique, the average hot air consumption is considerably high whereas no hot air is being consumed in cold pad-batch process which leads to energy conservation. However, the time employed for the fixation of eucalyptus leaves dye is very long in cold pad-batch technique. So, these techniques can be considered as best suitable for small scale industries or cottage dyeing of eucalyptus leave.

## **10. References**

76 Natural Dyes

Natural dyes cannot be used as simple alternatives to synthetic dyes and pigments. They do, however, have the potential for application, in specified areas, to reduce the consumption of some of the more highly polluting synthetic dyes. They also have the potential to replace some of the toxic, sensitizing and carcinogenic dyes and intermediates (Deo & Desai, 1999). Eucalyptus leaves, as natural dye, has greater potential because it is grown already on an

The effluent problems of synthetic dyes occur not only during their application in the textile industry, but also during their manufacture, and possibly during the synthesis of their intermediates and other raw materials. The application of synthetic dyes also requires metal salts for exhaustion, fixation, etc (Deo & Desai, 1999). Natural dyes, like eucalyptus leaves do not cause damage the environment by their extraction and many could be used satisfactorily without mordants, although it is true that the use of mordant improves the depth of shade for natural dyes. These mordants are normally metal salts and hence damage to the environment is still possible, albeit to a smaller extent than for synthetic dyes in textile applications. The research in this field has already identified a few "natural mordant", such as *Entada spiralis Ridl* (Chairat et al., 2007) and harda (*Chebulic myrabolan*) (Deo & Desai, 1999). The avoidance of metal-based mordants, or their replacement by natural mordants,

The authors would like to thank Ing. Martina Viková from the Technical University of

A wool fabric dyed in a solution containing the eucalyptus leaf extract showed a shade of pale yellowish-brown. The exception was when the fabric was dyed with the ferrous sulfate mordant, resulting in a shade of dark greyish-brown. The yield (exploitation) of the coloring component of eucalyptus leaf extract is good in wool fabric (about 68%–52% from the lowest to the highest concentrations). It can be observed that the *K/S* values increase with an increase of dye concentration. Little difference between the two padding techniques utilized for the wool fabric dyes by three mordanting methods, except wool fabrics mordanted with copper sulfate whose gave a high *K/S* values on the pad-batch technique than pad-dry technique. In all cases ferrous sulfate mordant yielded the best dyeing results, and the next good result was obtained in the order of copper sulfate, stannous chloride and alum. As observed from the *K/S* values, in the case of wool fabrics dyed with alum by using postmordanting method gave lower colour strength than without mordant. Alum and ferrous sulfate were the best mordant during simultaneous mordanting method of dyeing. However, copper sulfate showed the best mordant during simultaneous mordanting and pre-mordanting method of dyeing. For the *K/S* value on dyed wool fabrics were only little different using stannous chloride as mordant during three mordanting methods. The fastness properties ranged from good to excellent, while light fastness was fair to good. It

Liberec, Czech Republic, for testing of the UV transmission and UPF values.

**7. Potential of eucalyptus leaves dye 7.1 Potential commercial applications** 

**7.2 Potential effluent problems** 

**8. Acknowledgement** 

**9. Conclusions** 

industrial scale. It also shows good fastness on wool substrate.

may assist in the preservation of the environment.

Allen, R. L. M. (1971). *Colour chemistry*, Nelson, ISBN 01-77617-17-9, London, England


**5** 

*Spain* 

**Lipid Role in Wool Dyeing** 

Meritxell Martí, José Luis Parra and Luisa Coderch

*Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona* 

The textile industry uses different fibers obtained from various animals, of which the wool from domesticated sheep *Ovis aries* is commercially the most important. Dyeing is one of the most important finishing procedures of wool processing. It almost invariably involves absorption of water-soluble colorants from aqueous solutions by the fibers. Diffusion is the

Earlier workers studying the dye uptake of dyes by wool were mainly interested in the thermodynamics of the process, treating the wool fiber as a cylinder of uniform composition. Over the last decades there has been growing recognition of the importance of the diverse morphological structure of wool in determining its dyeing behavior (Rippon, 1992). Therefore a short wool structure description will be followed by a review of the role

The importance of the non-keratinous components of the fiber, specially the study of lipids present in the cell membrane complex prone us to emphasize in the lipid depleted wool, the modification of many properties and its behavior in the dyeing process. Besides the study of the mechanism of liposomes (made up with phospholipids) on wool dyeing could also help

Structurally, a wool fiber is an assembly of cuticle and cortical cells held together by the "cell membrane complex" (CMC). The surface of wool fibers consists of overlapping cuticle cells (Rippon, 1992). These are composed of two distinct major layers: the exocuticle and the endocuticle. The exocuticle consists of two sub-components, the A-layer, which is approximately 0.3 microns thick, and the B-layer, which is approximately 0.2 microns in thickness. These components differ mainly in the concentration of disulfide crosslinks (A-layer 35% half-cystine, B-layer 15% half-cystine

Individual cuticle cells are surrounded by a thin membrane, the epicuticle, which is approximately 3–6 nm thick and accounts for around 0.1% of the total mass of the fiber. Although the epicuticle is proteinaceous, the surface of clean, untreated wool is hydrophobic. This property is the result of a thin layer of fatty acids (lipids) which are

The cortex is made up of approx. 90% of keratin fibers, and is largely responsible for their mechanical behavior. It consists of closely packed overlapping cortical cells arranged

covalently bound to the surface of the epicuticle (the F-layer) (Naebe et al., 2010).

process by which the colorant molecules penetrate the interior of the fibers.

**1. Introduction** 

of this structure in wool dyeing.

**1.1 Wool structure** 

to elucidate the lipid role in wool dyeing.

and endocuticle 3% half-cystine).

