The present invention relates to a processing method of phase-transfer catalytic fixation on the textiles. More particularly, it relates to a processing method of phase-transfer catalytic fixation in supercritical carbon dioxide fluid using disperse reactive dyes for textiles, especially for natural-fibre textiles, belonging to the field of textile dyeing and finishing technology.
As one of the main industrial waste water discharger, traditional textile printing and dyeing industry is not only having high water resource consumption, but also producing a lot of wastewater. The wastewater produced by printing and dyeing is with complex and changeable composition, deep chromaticity, high COD value, and often contains a variety of toxic and harmful substances, which would pollute the fresh water resource and do harm to the ecological environment. Instead of dyeing with traditional water-bath, adopting and promoting the anhydrous ecological textile dyeing process in which supercritical carbon dioxide fluid is employed, has the characteristics of ecological effects, environmental protection and clean production, which facilitating the upgrading of traditional textile printing and dyeing industry and breaking through the bottleneck problem such as restricted by water and sewage. It is of far-reaching significance.
However, there are technical problems need to be solved of dyeing and fixing on textiles made of natural-fibres such as cotton, silk, wool, and the like, in supercritical carbon dioxide fluid. Due to the hydrophobicity of supercritical carbon dioxide fluid, it is greatly limited in the application of traditional ionic or high polarity dyes or/and auxiliaries. Additionally, hydrophilic fibres cannot be sufficiently wetted and swollen in hydrophobic supercritical carbon dioxide fluid. Therefore, the adsorption of dyes on fibres and diffusion of dyes in fibres are affected markedly. In recent years, many researchers have adopted different means or methods, and carried out extensive research in this field (cross-referenced the literatures: Dyeing of modified cotton fibres with disperse dyes from supercritical carbon dioxide Lewis J Soc Dyers Colour 114 5/6 (1998), pp. 169-173; Dyeing natural fibres with disperse dyes in supercritical carbon dioxide. Text Res J. 64 7(1994), pp. 371-374; Dyeing wool without water—possibilities and limits of supercritical CO2. In: Wenclawiak B, Padberg S, editors. 4th International symposium extraction for sample preparation-SFE-(X) SE-SPME-Book of abstracts 1999. Siegen: University GH of Siegen; 1999. p. 29-30; Modifying with TCT on silk and dyeing in supercritical carbon dioxide [J]. Silk, 2005(7):32-34). Existing technical researches and practices show that disperse reactive dyes which are structure-optimized can realize textile dyeing in supercritical carbon dioxide fluid. In particular, it is one of the feasible and effective ways to realize natural-fibre textiles dyeing and fixing (cross-referenced the literatures: Dyeing of cotton fabric with a disperse reactive dye in supercritical carbon dioxide, The journal of supercritical fluids, 2012, 69: 13-20; Solubility of disperse reactive dye in supercritical carbon dioxide, Colouration technology, 2012, 128: 127-132). As the parent structure of the dye has the hydrophobic properties of disperse dye, the problem of solubility of dyes in supercritical carbon dioxide fluid is solved effectively. At the same time, hydrophilic fibres can also get better adsorption and diffusion of dyes in the dry state without pretreatment such as wetting because the structure of the optimized dye is small. With certain conditions, the active groups in the dyes can react with the functional groups on fibres, so that dyes are connected with fibres by covalent bonds and fixed, greatly improving the colour fastness of the dyeing products.
However, because of the weak acidity of supercritical carbon dioxide fluid, the dyeing process of textiles, especially the dyeing and fixing of natural-fibre textiles is difficult to perform. Therefore, in order to improve the fixation efficiency, reduce the reaction temperature of fixation and shorten the processing time, etc., how to improve the reactivity of various functional groups on fibres in supercritical carbon dioxide fluid has very important significance.
The purpose of the present invention is to overcome the shortage of prior art and provide an effective processing method of textile dyeing and fixing in supercritical carbon dioxide fluid, especially for the natural-fibre textiles dyed by disperse reactive dyes.
A phase-transfer catalytic colour fixation processing method for textile, comprising the following steps:
1. Dry-dyeing with disperse reactive dyes on textiles in waterless supercritical carbon dioxide fluid;
2. Put the textiles into the phase-transfer catalytic fixation device, and take phase-transfer catalyst as the carrier of circulated supercritical carbon dioxide fluid, then the ionized fixing catalytic alkaline substance is transported from aqueous phase to hydrophobic supercritical carbon dioxide fluid phase, getting a good contact with functional groups on fibres, resulting in the fixing catalytic reaction with disperse reactive dyes. Ionized fixing catalytic alkaline substance is selected from sodium hydroxide, sodium carbonate and sodium phosphate, or the substances that can produce hydroxyl by hydrolysis or thermal decomposition in the environment with a small amount of water. The concentration of said fixing catalytic alkaline substance is 0.1 g/L˜20 g/L. Said phase-transfer catalyst is perfluorooctyl quaternary ammonium salt, or quaternary ammonium salt with C12˜C18 aliphatic chain or aryl group.
The active group of said disperse reactive dyes is selected from vinyl sulfone, ethenyl, triazine, nicotinic acid, or their derivatives.
In a preferred solution, the process of dry-dyeing on textiles in supercritical carbon dioxide fluid under anhydrous medium condition has the system pressure of 8.0˜30.0 MPa, temperature ranging at 40° C.˜100° C. and processing time for 30˜180 min.
In a preferred solution, the conditions of catalytic fixation reaction are temperature ranging at 60° C.˜160° C., pressure at 8.0˜30.0 MPa and time of reaction for 20˜180 min.
To realize said phase-transfer catalytic fixation processing method for textiles, a phase-transfer catalytic fixation device is used, which consists of the system of supercritical carbon dioxide fluid, fixing liquid storage tank and fixing reactor, wherein the fixing liquid storage tank is below the fixing reactor, and they are sealed connected by connecting device. Fixing liquid storage tank has a cylindrical cavity, in which there's a fluid distributor. Said fluid distributor is composed of several interconnected pipes, which bending down with the nozzles downward, and one of the pipes is used as circulated fluid inlet, connecting with said supercritical carbon dioxide fluid system, and the rest pipes are used as circulated fluid outlets. Said fixing reactor has a cylindrical cavity, with a circulated fluid outlet on the top, connecting with said supercritical carbon dioxide fluid system; moreover, a porous filter is installed at the bottom of the reactor, and the lower part of fluid diversion cover is horn shaped, covering at the top of the porous filter, and the top port of the fluid diversion cover is connecting with the opposite port of textile winding shaft. Said textile winding shaft is a cylindrical hollow shaft, whose top port is closed and holes are set on the cylinder.
With the above technical solution, the present invention has the following beneficial effects: due to the utilization of mechanism of phase transfer catalysis in the fixation system, when textiles, particularly the natural-fibre textiles, dyed and fixed by disperse reactive dyes in supercritical carbon dioxide fluid, alkaline accelerants that only can exist in the polar aqueous solution may also come into the hydrophobic fluid phase, and then react with the functional groups on the solid-phase fibres, which improving the reactivity of functional groups on fibres with dyes and increasing the dye catalytic fixation efficiency on fibres ultimately. Simultaneously, the process can reduce the temperature of fixing reaction and shorten the processing time. Thus, this invention has a broad application prospect in the aspect of textiles waterless dyeing and fixing process in the supercritical carbon dioxide fluid, especially for the natural-fibre textiles.
In
The present invention will be further described below with reference to drawings and embodiments.
In the process of textile phase transfer catalytic fixation provided by present invention, the textile adopted is a woven cotton fabric (102.0 g/m2) in dry state; the dye adopted is disperse reactive red (containing a active group of ethenyl, provided by Everlight Chemical Industrial Corporation, Taiwan, 0.2% o.m.f).
The phase transfer catalytic fixation device and the process provided by this invention can refer to China invention patent whose public number is CN102296469A named “the dyeing method of natural fibres in supercritical carbon dioxide fluid”.
Refer to
With reference to the steps and process above, analysis of dye fixation about disperse reactive red on cotton fabrics and the testing results are as follows:
For the sake of the analysis of fixation ratio of dyes on fabric, acetone is adopted in the fat extractor in order to extract the floating colour which is unfixed on fixed cotton fabric under the condition of 81° C. for 30 min. Moreover, the ratio of apparent colour depth values (K/S) which are before and after extraction is utilized to evaluate the dye fixation on fabrics. Fix (%) is the fixation efficiency of dye on the fabric, and it is calculated by the equation below.
Wherein
is the average of apparent colour depths value of the fabric sample after extraction (the arithmetic mean of the front end, side, in-middle-out on both sides of fabric; or named the fixation apparent colour depth value); n is the number of measurements (n=12 in this embodiment); (
According to the device and process of phase-transfer catalytic fixation provided in example 1, 11.00 g of the mixture (with 10% of solid contents; n(Na2CO3):n(FC-134)=3:1) of fixation accelerant (Na2CO3) and phase-transfer catalyst (FC-134) is added to the fixing liquid storage tank. The result refers to
According to the device and process of phase-transfer catalytic fixation provided in example 1, 13.75 g of the mixture (with 10% of solid contents; n(Na2CO3):n(FC-134)=3:1) of fixation accelerant (Na2CO3) and phase-transfer catalyst (FC-134) is added to the fixing liquid storage tank. The result refers to
According to the device and process of phase-transfer catalytic fixation provided in example 1, 16.50 g of the mixture (with 10% of solid contents; n(Na2CO3):n(FC-134)=3:1) of fixation accelerant (Na2CO3) and phase-transfer catalyst (FC-134) is added to the fixing liquid storage tank. The result refers to
According to the device and process of phase-transfer catalytic fixation provided in example 1, 19.25 g of the mixture (with 10% of solid contents; n(Na2CO3):n(FC-134)=3:1) of fixation accelerant (Na2CO3) and phase-transfer catalyst (FC-134) is added to the fixing liquid storage tank. The result refers to
According to the device and process of phase-transfer catalytic fixation provided in example 1, 22.00 g of the mixture (with 10% of solid contents; n(Na2CO3):n(FC-134)=3:1) of fixation accelerant (Na2CO3) and phase-transfer catalyst (FC-134) is added to the fixing liquid storage tank. The result refers to
According to the device and process of phase-transfer catalytic fixation provided in example 1, the system pressure is 8.0 MPa and temperature is 140° C. 11.00 g of the mixture (with 10% of solid contents; n(Na2CO3):n(FC-134)=3:1) of fixation accelerant (Na2CO3) and phase-transfer catalyst (FC-134) is added to the fixing liquid storage tank (2). The result shows in table 1.
Table 1 is the result of disperse reactive red dye (0.2% o.m.f) on cotton woven fabric performed as phase-transfer catalytic fixation process provided by present example.
Table 1 shows that, a good dyeing effect is obtained for disperse reactive red dye on the dry cotton woven fabric in supercritical carbon dioxide fluid, and with the help of phase transfer catalyst in the low-pressure supercritical carbon dioxide fluid which is in near critical state, fixation accelerant can facilitate the fixation reaction of functional groups on fibres with dyes and improve the fixation apparent colour depth value (
According to the device and process of phase-transfer catalytic fixation provided in example 1, the system pressure is 20.0 MPa and temperature is 160° C. 11.00 g of the mixture (with 10% of solid contents; n(Na2CO3):n(FC-134)=3:1) of fixation accelerant (Na2CO3) and phase-transfer catalyst (FC-134) is added to the fixing liquid storage tank (2). The result shows in table 2.
Table 2 is the result of disperse reactive red dye (0.2% o.m.f) on cotton woven fabric performed as phase-transfer catalytic fixation process provided by present example.
Table 2 indicates that with the help of phase-transfer catalyst, fixation accelerant also can get in touch with the fabric, facilitating the fixation reaction of functional groups on fibres with active groups of dyes, and improve the fixation apparent colour depth value (
According to the device and process of phase-transfer catalytic fixation provided in example 1, the system pressure is 12.0 MPa and temperature is 140° C. 16.50 g of the mixture (with 10% of solid contents; n(Na2CO3):n(FC-134)=3:1) of fixation accelerant (Na2CO3) and phase-transfer catalyst (FC-134) is added to the fixing liquid storage tank (2). Fixation processing for 40 min, 60 min and 100 min have been done respectively, and the treatment time ratio of fluid circulation alternating with static is 1:5. The result shows in table 3.
Table 3 is the result of disperse reactive red dye (0.2% o.m.f) on cotton woven fabric with different times of phase transfer catalytic fixation process provided by present example.
Table 3 depicts that dyeing with phase-transfer catalytic reaction in supercritical carbon dioxide fluid, the fixation apparent colour depth value (
From the fixation effect of example 1 to example 9, it is indicated that textiles dyed by disperse reactive dyes, especially the natural-fibre textiles such as cotton, when using phase-transfer catalysis in fixing stage, accelerant in the fixing mixture comes into the hydrophobic fluid phase along with mass transfer with the fabric; as a consequence, the reactivity of functional groups on fibres is improved so as to facilitate the fixing reaction of dyes and fibres, and also effectively improve the apparent colour depth value (
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/CN2013/082832 | 9/3/2013 | WO | 00 |