Application of calix[4]arene and calix[4]resorcinarene dyes CHAPTER 3

Transcription

1 Application of calix[4]arene and calix[4]resorcinarene dyes CHAPTER 3

2 Abstract: The synthesized calix[4]arene and calix[4]resorcinarene dyes have been studied for their spectral properties and application as colorants in offset and Lithographic printing inks. The effect of acid and base as well as solvents on the absorption spectra of the dyes has been analyzed. The proton ionization constants and oscillator strength of the dyes were calculated and the dyes were then used as colorants for solvent based offset and Lithographic printing inks while water soluble dyes has been applied to leather, wool, silk and cotton for dying. Various properties such as water fastness, light fastness, acid-perspiration and alkaline-perspiration after applied on cotton, coated and uncoated paper were also studied. Page 60

3 Introduction: Calix[n]arenes represent macrocyclic compounds widely used in supramolecular chemistry for the construction of various receptors for the complexation of charged or neutral molecules [1]. Their unique three-dimensional structures with almost unlimited derivatization abilities and a tuneable shape of the molecules make calixarenes ideal candidates for building blocks and/or molecular scaffolds in the design of new more sophisticated molecules. Calixarenes have several attractive features as macrocycles of higher degree of preorganization. They are formed by paraphenolic units linked by methylene bridges ortho to the OH functions. Calixarene can be chemically modified by substitution of the phenolic hydrogens with various types of functions known for their affinity of the cation of interest [2]. Furthermore, phenolic groups can be functionalized on the para position to make the calixarene either lipophobic or lipophilic. In recent years several workers have reported modified macrocycles calixarenes with chromogenic groups. Among the derivatives of calixarenes, the azo functionalized calixarenes have been widely studied for their chromogenic effects. Azocalixarenes have been mainly studied: calixarenes bridging phenylazo moieties on the upper rim [3-4] and lower rim [5], double azocalixarenes [6], and azocalixcrowns [7]. The inner space of azocalixarenes molecules provides a unique microenvironment to the included guest species. The azo group is not only known for its metal binding abilities, but this group is also widely utilized in the field of dyes and pigments. This group has versatile applications in various fields such as the dying of textile fiber, coloring of different materials, such as plastics, and some biomedical uses. There are Page 61

4 many patents and papers describe the synthesis and dying properties of azo compound [8-9]. In recent years, digital printing has emerged as a strong growth technology. The world of digital printing encompasses many technologies, including computer to print, such as electrophotography, xerography, and ink jet, which employs no intermediate carrier - such as a plate - on which the image, in whole or part, is fixed. If the digital data changes, the image changes, so that conceptually - and increasingly in practice - every sheet can be different. A dye or a dyestuff is usually a colored organic compound or mixture that may be used for imparting color to a substrate such as cloth, paper, plastic, or leather in a reasonably permanents fashion. Azo dyes and pigments constitute the largest and most varied group of synthetic organic colorants in use today. They have characteristically good tinctorial strength as well as stability and their preparation procedures, by the classic diazotization and coupling reactions, are very simple and of low cost. Hence, in addition to their conventional application as colorants for wools, fabrics, prints, inks, and toners, azo compounds have also found their way into hightechnology areas, such as colorants for liquid-crystalline materials and as photoconductors for photoreceptors in copiers and laser printers [10-11]. With the increased usage of these azo colorants, there is an increasing demand to modulate their features and obtain colorants having enhanced permanence, solubility and stability. This can be achieved by specific modifications of the dye structure, in particular by increasing the molecular weight of the dyes with bulky organic groups known as ballast group. Page 62

5 A survey of the recent literature reveals that calix[4]arenes and calix[4]resorcinarene have been mostly studied for their complexation properties with metal ions as well as for the host-guest complexes formed with neutral organic molecules. In recent years very few macrocycles such as crown ethers and calixarenes have been used as components for the preparation of azo dyes. Calix[n]arenes have been mostly reported as the coupling component for various diazotized aromatic amines [12-14]. However, only few reports have appeared with literature so far, which were from our department, wherein derivative of calix[4]arenes and calix[4]resorcinarene have been used as the active coloring materials [4, 19-22]. Hence, the present investigation was undertaken, with an aim of studying the dyeing possibilities of calix[4]arenes and calix[4]resorcinarene based dyes on leather, fiber and also as offset and Lithographic printing inks. Lithography is an "offset" printing technique. Ink is not applied directly from the printing plate (or cylinder) to the substrate as it is in gravure, flexography and letterpress. Ink is applied to the printing plate to form the "image" (such as text or artwork to be printed) and then transferred or "offset to a rubber "blanket". Offset printing process Page 63

6 The image on the blanket is then transferred to the substrate (typically paper or paperboard) to produce the printed product. Offset printing is a widely used printing technique where the inked image is transferred (or offset ) from a plate first to a rubber blanket, then to the printing surface. When used in combination with the lithographic process, which is based on the repulsion of oil and water, the offset technique employs a flat (planographic) image carrier on which the image to be printed obtains ink from ink rollers, while the non-printing area attracts a film of water, keeping the nonprinting areas ink-free. In the present investigation, the possibility of using calix[4]arene and calix[4]resorcinarene as ballast for azo dyes was explored. Hence a series of calix[4]arene and calix[4]resorcinarene based azo dyes were synthesized as described in Chapter 2 by the coupling calix[4]arene and calix[4]resorcinarene with different aromatic amino groups. The spectral properties of the dyes were studied and since the synthesized dyes were found to be soluble in almost all organic solvents they were used as active coloring agents in offset and Lithographic printing inks. These are basically solvent-based inks which are printed using the offset and Lithographic printing inks process. Further, calix[4]resorcinarene azo dyes were used for the first time, for dyeing on leather as well as for dyeing on woolen, nylon and cotton fabrics. Page 64

7 Experimental: Chemical and Reagents All the chemicals used were of analytical reagent grade of BDH, E-Merck or Qualigens unless otherwise specified. The solvents used for absorption studies were rigorously purified by standard procedures [15]. Instrumentation Melting points were taken on Veego (VMP-DS) using a Mel-Temp apparatus. Electronic spectra were recorded on a Jasco-570 UV-visible spectrophotometer with matching 10 mm quartz cells. Decomposition temperatures were determined using a Shimadzu DSC 60 differential scanning calorimeter with a heating rate of 10.0 ºC min -1 in air and it was calibrated with indium (156.6 ºC, Jg -1 ). Synthesis of Dyes The synthesis and characterization of calix[4]resorcinarene dyes (d 1 -d 5 ) and calix[4]arene (d 6 -d 8 ) were as reported in Chapter 2. General Procedure for Spectral studies For the spectral studies M dye (d 1 -d 8 ) solutions in various solvents were used and the effect of acid and base was studied by addition of 0.1 M sodium hydroxide and 0.1 M hydrochloric acid respectively. Page 65

8 General procedure for proton ionization constants For pka measurements, M (DMF) dye (d 1 -d 8 ) solutions in the ph range of 2-13 were made and the spectra were recorded at 25 0 C in the range of nm. The ionization constants were then calculated using the following equation: pka ph log 10 A Ab Aa A pka ph where, Δ log 10 A Ab Aa A A is the absorbance at the specific ph, Aa and Ab are the absorbances for the most acidic and most basic ph, respectively. The ionization constants were also determined graphically by plotting a graph of ph Vs, wherein the intercept gave the value of the ionisation constant [16]. General Procedure for the preparation of inks A fluid usually coloured and capable of very rapid application by a printing press. Inks must dry to a handle coating providing multiple images on a wide variety of substates. A typical solvent-based ink formulation consists of: Resin to impart body to the ink and for adherence of the ink to the substrate Solvents to adjust the viscosity and provide flow to the ink Dyes or pigments to impart color to the ink Page 66

9 Additives such as driers, catalyst, waxes and print performance modifiers The required components are mixed in appropriate quantities and shaken in vibroshaker container with glass beads to have uniform mixing. The synthesized dyes were also used for formulating solvent based inks [18]. Offset ink for aluminum foil To a mixture of dye (3g) and nitrocellulose resin (9g) was added maleic resin (4g), wax dispersion (2g), (3g) and glass beads (120g) and the mixture was shaken for 40 min. Lithographic ink for coated and uncoated paper To a mixture of substance (12g), alcohol soluble maleic resin (50g) and glycol ether (8g) in a vibroshaker container was added ethanol (120ml) and glass beads (160g) and mixture was shaken for 40 min Procedure of woolen dyeing Taken a 0.1 g of dye (d 1, d 2 ) dissolved in 100 ml of distilled water (0.1% solution), stirred this solution at 40 0 C for 5 min and then added 2.5 g woolen cloth and heated it to C for 30 min and then added 2.5 ml acetic acid and maintained the temperature to about C for 30 min. Washed the woolen cloth with distilled water and dried. Same procedure we adopted for the dyeing of the nylon, silk and cotton material. Page 67

10 Procedure of leather dyeing Leather treatment Taken a small piece of cow full chrome leather in a 500 ml of distilled water and stirred it for 30 min. There after taken out the leather and washed with distilled water and put it in to a beaker containing 25 ml 2% sodium formate and 25 ml 2% sodium bicarbonate stirred it for 60 min. The leather was taken out and washes with distilled water. This leather is now ready for dyeing. Leather dyeing Taken a 0.2 g of dye (d 1, d 2 ) dissolved in 100 ml of distilled water (0.2% solution) stirred this solution at 60 0 C for 15 min, added leather piece into it and stirred it at 70 0 C for min, then added 5 ml 10% formic acid and stirred it for 30 min. Taken out the leather piece and washed with distilled water and dried. Page 68

11 Results and Discussion: Thermal Properties The decomposition temperatures of all the dyes (d 1 -d 8 ) were taken from the DSC curves of the dyes. The temperature at which the dyes first exothermic peak starts appearing after the melting point was taken as the decomposition temperature. The melting points and decomposition temperatures of all the synthesized dyes are as shown in Table 1. All prepared dyes showed high melting points (mp o C) and subsequently high thermal stability. The DSC curves of all dyes d1-d8 are shown Figure DSC mw Temperature 0 C M.P C Decomp. temp. ~ C Figure 1: DSC curve for d 1 Page 69

12 DSC mw Temperature 0 C M.P C Decomp. temp. ~ C Figure 2: DSC curve for d 2 DSC mw Temperature 0 C M.P C Decomp. temp. ~ C Figure 3: DSC curve for d 3 Page 70

13 DSC mw Temperature 0 C M.P C Decomp. temp. ~ C -20 Figure 4: DSC curve for d 4 DSC mw Temperature 0 C M.P C Decomp. temp. ~ C Figure: 5 DSC curve for d 5 Page 71

14 DSC mw Temperature 0 C M.P C Decomp. temp. ~ C Figure 6: DSC curve for d 6 DSC mw Temperature 0 C M.P C Decomp. temp. ~ C Figure: 7 DSC curve for d 7 Page 72

15 DSC mw Temperature 0 C M.P C Decomp. temp. ~ C Figure 8: DSC curve for d 8 Solvent Effect The absorption spectra of azocalix[4]resorcinarene (d 1 d 5 ) and azocalix[4]arenes (d 6 d 8 ) were recorded in various solvents at a concentration of to M; the results are summarized in Table 1. The electronic absorption spectra of azocalix[4]arene and azocalix[4]resorcinarene derivatives (d 1 d 8 ) exhibited one absorption band *ߨ n and *ߨ ߨ in the range nm corresponding to transitions which is in accordance with typical diazo spectra. The visible absorption spectra of the compounds were found to exhibit strong solvent dependency, which did not show regular variation with the polarity of the solvents. Strong evidence for the existence of these compounds existing in an equlibrium is provided by the isosbestic points in the visible spectra of, for example, compound d 3 in different solvents (Figure 9). This equilibrium may exist between tautomeric forms. The equilibrium depends on the basicity of the solvents used; in proton accepting solvents such as DMSO, DMF, acetonitrile, chloroform and methanol, the compounds displayed a red shift of λ max. Page 73

16 The effect of concentration of the compound on absorption maxima was examined (Table 2). The λ max of all compounds did not change with compound concentration which also indicates that azocalix[4]arenes exist in their tautomeric form in all solvents used. Absorbance DCM MeOH DMSO CHCl3 DMF CH3CN Wavelength (nm) Figure: 9 Absorption spectra of the azocalix[4]arene d 3 in various solvent Effect of Acid and Base The effect of acid and base on the absorption of the dye solutions was investigated and the results are shown in Table 3. With the addition of base (0.1 M sodium hydroxide), the λ max of the dyes showed a hypsochromic shift along with a shoulder at longer wavelength. The λ max of the compounds in methanol also showed slightly hypsochromic effects with addition of acid (50% HCl). The azocalix[4]arenes may exist in two possible tautomeric forms, namely an azoenol form A and keto-hydrazo form B as shown in Figure 10. Page 74

17 N N N N N N N N H N N H N N N N H N N H OHOH HO HO O O O O A B Figure 10: The tautomeric form of the synthesized dye. The effect of concentration of the compound on absorption maxima was examined. The λ max of all compounds did not change with compound concentration. Oscillator strength The spectral details of the synthesized calix[4]arene and azocalix[4]resorcinarene dyes (d 1 d 8 ) are summarized in Table 4. The dyes showed colors ranging from red (λ max 457 nm) to yellow (λ max 356 nm). The different substituents are in positions slightly away from the chromophoric systems. Hence they may not directly influence the absorption maxima. But the general observation made is that most of the substituted dyes have higher absorption maxima when compared to their unsubstituted analogues. The molar extinction coefficient (ε max) of the dyes showed that most of them are intensely absorbing. However, it is the oscillator strength (ƒ) that gives a full measure of the tinctorial strength rather than molar extinction coefficient (ε max) [11, 17]. Hence, the oscillator strength was calculated using the following equation: ƒ = ν 1/2 ε max where ƒ is oscillator strength, ε max is the molar extinction coefficient at maximum absorption, ν is the full width at half maximum of the absorption curves for the dyes. Page 75

18 It can be seen from Table 4 that dyes d 1 and d 3 showed high value of oscillator strength. Proton Ionization Constants The ionization constants are a center property of a molecule which reflects its structural characteristics, reactivity, spectral properties and the isolation conditions. From the values of the ionization constants summarized in Table 5 it can be easily concluded that dye d 1 and d 2 is the most acidic in nature. This implies directly that of all the synthesized dyes, dyes d 1 and d 2 have more tendencies to be taken up in an aqueous solution than into organic solvents. Hence it will have comparatively less solvent solubility and water fastness than the other dyes. Fastness Properties The light fastness of the dyes on d 3 - d 8 substrates uncoated paper was in the range of 4-6 (fairly good to good) while the wet fastnesses on d 3 - d 8 substrates were in the range of 4-6 (fairly good to good). The light fastness on uncoated paper and coated paper is summarized in Table 5. Water soluble dyes d 1 and d 2 were used for dyeing silk, leather, cotton and wool. The fastness testing involving dyed silk, leather, cotton and wool on wet fastness, wash fastness, light fastness and perspiration fastness is summarized in Table 6-8. The dyes d 1 and d 2 showed promising results for leather dyeing. The dye d 3 gave best results for coated and uncoated paper while d 5 was found most suitable for aluminum foil. For polyester film, d 8 gave best results. Page 76

19 Conclusion: A series of novel calix[4]arene dyes were used for Offset printing and Lithographic printing process and a series of novel calix[4]resorcinarene dyes were used for dyeing on wool, silk, leather and cotton. The synthesis, characterization, absorption spectra and the industrial application of a series of azocalix[4]arene and calix[4]resorcinarene compounds. The dyes were all stable up to C and hence can be effectively used in almost all kinds of inks. Page 77

20 Table 1: Physical characteristics of the dyes (d 1 d 8 ) Dye Melting point ( 0 C) Decomposition Temperature ( 0 C) d > 300 d > 300 d > 250 d > 270 d > 270 d > 260 d > 250 d > 250 Table 2: Solvatochromic properties of the dyes (d 1 d 8 ) Dye λ max (nm) DMSO DMF CH 3 CN Methanol DCM CHCl 3 d d d d d d d d Page 78

21 Table 3: Effect of acid and base on the dyes (d 1 d 8 ) Dye λ max (nm) Methanol λ max (nm) Methanol N NaOH λ max (nm) Methanol HCl d , 392 (s) d , 492 (s) 338 d , 520 (s) 402, 430 (s) d , 445 (s) 361, 505 (s) d , 540 (s) 389, 525 (s) d , 515 (s) 401, 424 (s) d , 460 (s) 376, 454 (s) d , 492 (s) 393 Table 4: Oscillator strength for the dyes (d 1 d 8 ) Dye λ max (nm) (DMF) ΔV 1/2 (cm -1 ) ε max (L mol -1 cm -1 ) F d d d d d d d d Page 79

22 Table 5: Ionization constants of the dyes Dye Ionization constant (Calculated) pk a Ionization constant (Graphical ) pk a d ± d ± d ± d ± d ± d ± d ± d ± Page 80

23 Table 5.1: Proton ionization constant of dye d 1 ph Absorbance Δ pk a Average pk a : 5.85 ± Δ ph Intercept: 5.85 Page 81

24 Table 5.2: Proton ionization constant of dye d 2 ph Absorbance Δ pk a Average pk a : 6.27 ± Δ ph Intercept: 6.29 Page 82

25 Table 5.3: Proton ionization constant of dye d 3 ph Absorbance Δ pk a Average pk a : 8.90 ± Δ ph Intercept: 8.89 Page 83

26 Table 5.4: Proton ionization constant of dye d 4 ph Absorbance Δ pk a Average pk a : 8.06 ± Δ ph Intercept: 8.08 Page 84

27 Table 5.5: Proton ionization constant of dye d 5 ph Absorbance Δ pk a Average pk a : 7.52 ± Δ ph Intercept: 7.52 Page 85

28 Table 5.6: Proton ionization constant of dye d 6 ph Absorbance Δ pk a Average pk a : 9.47 ± Δ ph Intercept: 9.48 Page 86

29 Table 5.7: Proton ionization constant of dye d 7 ph Absorbance Δ pk a Average pk a : ± Δ ph Intercept: Page 87

30 Table 5.8: Proton ionization constant of dye d 8 ph Absorbance Δ pk a Average pk a : ± Δ ph Intercept: Page 88

31 Table 6: Fasteness studies of the dyes Dye Washing Light fastness Wet fastness Leather Wool Silk Cotton Leather Wool Silk Cotton Leather Wool Silk cotton d d Table 7: Fasteness studies of the dyes Dye Aluminium foil Polyester film Uncoated paper Coated paper Light fastness Wet fastness Light fastness Wet fastness Light fastness Wet fastness Light fastness Wet fastness d d d d d d Table 8: Fasteness studies of the dyes Dye Acid-perspiration Alkaline-perspiration Leather Wool Silk Cotton Leather Wool Silk Cotton d d where, 1 is very poor, 2 is poor, 3 is moderate, 4 is fairly good, 5 is good, 6 is very good,7 is excellent and 8 is outstanding. Page 89

32 Figure 1: A typical drawdown of the inks of dye d 3 on coated paper, uncoated paper aluminium foil. Figure 2: A typical drawdown of the inks of dye d 8 on aluminium foil, polyester film uncoated paper. Page 90

33 Figure 3: A typical drawdown of the inks of dye d 5 on coated paper, uncoated paper polyester film. Figure 4: leather dyeing of dyes (d 1 -d 2 ) Page 91

34 Figure 5: Dyeing of nylon and silk of dye d 1 Figure 6: Dyeing of woolen of dye d 2 Page 92

35 References: 1) C. D. Gutsche, J. F. Stoddart, Ed, The Royal Society of Chemistry, Cambridge. (1989). 2) J. H. Bok, H. J. Kim, J. W. Lee, S. K. Kim, J. K. Choi, J. Vicens, Tetrahedron Lett.,(2006), 47(8), ) J. D.van Loon, A. Arduini, W. Verboom, R. Ungaro, G. J. van Hummel, S. Harkema, D. N. Reinhoudt, Tetrahedron Lett., (1989), 30(20) ) S. K. Menon, R. Patel, J. Panchal, J. Incl. Phenom. Macroc. Chem., (2010), 67, ) P. Jose, S. K. Menon, Bioinorg Chem Appl., (2007) 6) H. M. Chawla,G. Hundal, S. P. Singha, S. Upreti., Cryst Eng Comm., (2007), 9, ) F. Karci, N. Ertan, Dyes Pigm., (2002), 55(2-3), 99. 8) K. Tanaka, K. Matsuo, A. Nakanishi, J. Shiota, M. Yamaguchi, S. Yoshino, K. Kawaguchi., Chem. Pharm. Bull., (1984), 32, ) A. E. Visser, S. T. Griffin, D. H. Hartman, R. D. Roger., Journal of Chromatography B: Biomedical Sciences and Applications., (2000), 743, ) H. Zollinger, Color Chemistry, Weinheim, Wiley-VCH., (2003). 11) P.F. Gordon and P. Gregory, Organiv Chemistry in Color, New York Springer-Verlaf, (1983). 12) H. Deligoz, I. Senner and F. Karci, Dyes Pigm.,(2004), 59, ) H. Deligoz, I. Senner and F. Karci, Dyes Pigm., (2004), 62, ) H. Deligoz, I. Senner, F. Karci, E. Kilic, Dyes Pigm., (2004), 62, ) B. S. Furniss, A. J. Hannaford, P. W. G. Smith, A. R. Tatchell,Vogel s Textbook of Practical Organic Chemistry. London: Longman., (2004). 16) Y. K. Agrawal, B. R. Pandya., Ind. J. Chem. Tech., (2002), 9, 6. 17) J. P. Kim, S. Kim, J. Koh., Color Technol., (2004), 120, ) National Institute of Industrial Research Board. Modern Technology of Printing and Writing Inks. New Delhi:Asia Pacific Business., (2001). 19) V. K. Jain, P. H. Kanaiya, and N. Bhojak, Fibers and Polymers., (2008), 9(6), 720. Page 93

36 20) V. K. Jain, S. G. Pillai and P. H. Kanaiya, Eu. Journal of Chemistry., (2008), 5(5), ) V. K. Jain, H. C. Mandalia, J. Inclu. Phenom. Macrocyclic. Chem., (2009), 63, ) V. K. Jain, H. C. Mandalia and N. Bhojak, Fibers and Polymers., (2010), 11(3), 363. Page 94