In the textile industry, in the various processing steps from spinning, spinning, weaving, printing and dyeing to finished products, different auxiliary chemicals are used according to the performance of various fibers to improve the quality of textiles, improve processing results, increase production efficiency, and simplify Process, reduce production costs and give textiles various excellent application properties. This auxiliary chemical is commonly known as textile dyeing and finishing auxiliary.
Textile additives have an indispensable and important role in improving the product quality and added value of textiles. It is a necessary chemical in the production and processing of textiles. It can not only give textiles a variety of special functions and styles, such as softness, wrinkle resistance, shrinkage resistance, waterproof, antibacterial, antistatic, flame retardant, etc., but also improve the dyeing and finishing process, play a role in saving energy and reducing processing costs. Textile auxiliaries are essential to improve the overall level of the textile industry and its role in the textile industry chain.
At present, there are nearly 100 textile auxiliaries worldwide, producing nearly 16,000 varieties, with an annual output of about 4.1 million tons. Among them, there are 48 categories and more than 8,000 varieties of textile additives in Europe and America; there are 5,500 varieties in Japan. According to reports, in 2004 the world textile additives market sales reached 17 billion US dollars, far exceeding the sales of the dye market that year. There are about 2,000 manufacturers of textile additives in China, mostly private enterprises (8-10% of joint ventures and wholly-owned enterprises), mainly concentrated in Guangdong, Zhejiang, Jiangsu, Fujian, Shanghai, Shandong and other provinces and cities. The textile additives produced in China can meet 75-80% of the domestic textile market demand, and 40% of the production of domestic textile additives is exported to foreign countries. However, domestic textile auxiliaries are still far behind the international advanced level in terms of variety and quality, as well as in synthesis and application technology. Special and high-end textile auxiliaries still have to rely on imports.
About 80% of textile auxiliary products are based on surfactants, and about 20% are functional additives. After more than half a century of development, the surfactant industry worldwide has matured. In recent years, the production center of the textile industry has gradually shifted from traditional Europe and the United States to Asia due to well-known reasons, resulting in a rapid increase in the demand for textile additives in the Asian region.
The basic safety requirements of today's textile additives
In today's international market, there are strong demands on textiles for safety and ecology.No matter how different the various certification systems and various textile companies have these requirements, in order to facilitate consumer identification and purchase, the safety of textiles has basic Requirements, that is, meet the following six requirements: (1) no VOC (no volatile organic compounds); (2) no FA or low FA (no formaldehyde or low formaldehyde); (3) no DS (no hazardous chemicals) Substance); (4) No EH (no environmental hormones); (5) No PFOS and PFOA (no PFOS and sulfonylate and perfluorooctanoic acid); (6) No AOX (no adsorbable organic halide) This is also the basic safety requirement for textile additives used in domestic and foreign markets, which means that for general environmental protection and human health considerations, textile additives should not contain VOC, FA, DS, AOX, EH, PFOS and PFOA.
1. No VOC
VOC refers to volatile organic compounds such as toluene, xylene, styrene, vinylcyclohexane, phenylcyclohexane, butadiene, vinyl chloride, formaldehyde, fragrance, gasoline, kerosene, white essential oil and polycyclic aromatic Group hydrocarbons (such as tar), etc., which will cause great harm to human health and the surrounding environment, so many foreign countries have formulated VOC regulations.At present, the world's most comprehensive VOC regulations are the CleanAir Act of the United States, the European Union , Switzerland, etc. also have VOC rules. In order to have a judgment on the amount of VOC in the additives, it must be quantitatively analyzed. The olfactory judgment method is not enough and inappropriate for the safety of the human body or the accuracy of the measurement. .At present, VOC is defined internationally as a compound composed of carbon element combined with one or more nitrogen, oxygen, hydrogen, sulfur, phosphorus, silicon or halogen (fluorine, chlorine, bromine, iodine) at 20 ℃ or under operating conditions. Its vapor pressure exceeds 0.01 kPa and no chemical changes occur. In addition to considering the vapor pressure of chemical substances, Switzerland also stipulates that the boiling point at standard pressure is ≤240 ° C and no chemical changes occur. This is the basis of VOC quantitative analysis and is usually used instrument The analysis is carried out together. Textile coating printing is processed with a large amount of VOC. The original paste-like synthetic thickener used has a mineral oil content of 35% to 65%, and the VOC amount greatly exceeds the limit allowed by regulations, so powder has been developed. Although the VOC content has decreased from 35% to 65% to 4% to 6%, the processability (such as solubility and swellability) is relatively poor and the dust is easy to fly. It is difficult to control and adjust the viscosity of the paste, and the gel particles will be blocked due to insufficient expansion, which makes the powder thickener popularized slowly in the market. The newly developed VOC-free natural oil is used as the base carrier. The new paste-like synthetic thickener not only solves the problem of VOC, but also has a series of advantages of paste-like synthetic thickener (containing mineral oil). Representative products include Swiss CHT's Tubivis ECO 650 and Tubivis ECO 400, the former is an economical Good quality products, the latter can meet the highest technical requirements including electrolyte stability, permeability and clarity of printed contours. At present, there are no similar products in China. Since such a difficult VOC problem has been found and solved The way, other VOCs of textile additives ask It should not be difficult to solve.
2. No EH
Among the 70 environmental hormones (EH) recognized on the international market, the environmental hormones related to textile additives include polychlorinated biphenyls, alkylphenols, polychlorinated dibenzo-p-dioxins, phthalate compounds, Chlorinated phenol, organotin compounds, benzophenone and p-nitrotoluene, etc. 26 kinds, accounting for 37% of the number of environmental hormones. These environmental hormones enter the textile auxiliaries in different ways: (1) Used as raw materials; (2) As a final product; (3) Produced as a by-product during the preparation of additives; (4) Produced when the product is subjected to high temperatures or burning. In recent years, a considerable part of the problems found during the testing of China's textiles are related to Environmental hormones are related, the first is the alkylphenol polyoxyethylene ether (APEO) directly related to the environmental hormone alkylphenol; the second is the environmental hormone phthalate compounds, which are mainly used for Coating finishing, soft finishing, plastisol printing and paint dyeing, etc.At present, the annual output of phthalate compounds in China is very large, about 1.5 million tons, and the apparent consumption is 1.4 million tons. Some substitutes such as polyol benzoate have been developed, but the performance is still To be improved; the third-ranked environmental hormone is organotin compounds, including monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), tetrabutyltin (TeBT), tricyclohexyltin phosphate (TCyHT), and Octyl tin (MOT), dioctyl tin (DOT), trioctyl tin (TOT), triphenyl tin (TPhT), tripropyl tin (TPT), etc.A total of 10 varieties, there are mainly 6 varieties namely DBT, TBT, TCyHT, TOT, TPhT and TPT. At present, they are no longer used as bactericides on textiles except for being used as catalysts, polymer stabilizers or when they are taken to textiles during anticorrosive coatings during monomer polymerization. Obviously, it is still difficult to achieve EH-free textile additives.It is necessary to strengthen the technical innovation and development of new products, strengthen management and testing, and eliminate sources of pollution. The current focus is to solve alkylphenol polyoxyethylene ethers. And the substitution of phthalate compounds.
3. No DS
DS refers to hazardous chemicals, with a low ignition point, for example, the ignition point of acetone is -20 ℃, it is a hazardous chemical. At present, in order to ensure that textile additives do not contain hazardous chemicals, high ignition is used Point, safe chemicals to prepare, such as the ignition point of dipropylene glycol methyl ether is 74 ℃, the ignition point of tripropylene glycol methyl ether is 135 ℃, the ignition point of hexanediol is 110 ℃, etc., use them to replace acetone It is safer to prepare textile additives. Another example is that the ignition point of kerosene is low, and the emulsified thickening slurry prepared with it is flammable, explosive, and dangerous, and now it is synthesized by mineral oil-free or low-mineral oil. It is replaced by thickener, which greatly improves the safety of paint printing.
4. No PFOS and PFOA
Both PFOS and PFOA are organic fluorine compounds. At present, the restrictions on them in the international market are very strict, which is a safety issue worthy of attention in today's textile additives.
5. No FA or low FA
Regarding the content of formaldehyde (FA) in textile auxiliaries, regulations have been promulgated at home and abroad for a long time.Recently, many regulations and standards on the international market and the restrictions on chemical form of brand textile sellers have stricter requirements on formaldehyde content. In accordance with these requirements, domestic and foreign textile auxiliary manufacturers have developed many low formaldehyde (formaldehyde content <75 × 10-6) and formaldehyde-free additives to replace formaldehyde-containing additives, including color fixing agents, anti-wrinkle and anti-iron Finishing agents, adhesives, cross-linking agents, dispersants, flame retardants and waterproof and oil-repellent finishing agents, etc. From the current situation analysis, there is a certain basis for replacement, it is possible to achieve textile additives without formaldehyde or low formaldehyde .
6. No AOX
AOX is the English abbreviation for adsorbable organic halide, which refers to the organic halide that can be adsorbed with activated carbon. Because AOX will react under certain conditions to produce polyhalogenated dibenzo-p-dioxin (PHDDO) and polyhalogenated dibenzo Furan (PHDF) and other carcinogens, so it is very harmful to human health and the ecological environment. Many varieties of textile additives belong to AOX, which can be summarized into the following five categories: (1) halogen-containing organic carriers, such as two Chlorobenzene, trichlorobenzene, monochlorotoluene, dichlorotoluene, trichlorotoluene, etc .; (2) chlorinated hydrocarbon solvents, such as 1,1,1-trichloroethane, 1,2-dichloroethane, 1 , 1-dichloroethylene, trichloroethylene, 1,3-dichloropropene, tetrachloroethylene, carbon tetrachloride, etc .; (3) halogen-containing finishing agents, such as halogen-containing flame retardants, TRIS is tri- (2 , 3-dibromopropyl) phosphate, PBB is polybrominated biphenyl, PBDPE is pentabromodiphenyl ether, OBDPE is octabromodiphenyl ether, etc., there are at least more than 10 commonly used varieties on the market at present; anti-shrink finishing agent is wool Anti-shrinking finishing agents, etc .; mothproofing agents include Mitin FF, Eulan U33, mothproofing agent N, etc .; halogen-containing insecticides include DDT (dichlorodiphenyltrichloroethane), etc .; anti-mold preservatives include pentachlorophenol; Halogen-containing fungicide has mildew net ASM that is 5,5 -Dichloro-2,2'-dihydroxydiphenylmethane, etc., involving a total of 30 to 40 important finishing agent varieties on the market; (4) halogen-containing pretreatment agents, such as halogen-containing scouring agents include chlorofluoroolefin solvents Etc., and chlorine bleach, etc .; (5) PVC.
At present, it is still difficult to use halogen-free organic compounds in textile auxiliaries.For example, in recent years, several halogen-free carriers have been developed to replace halogen-containing organic carriers such as N-methylphthalimide and N-naphthyl Leimide, dipropanol (Procar DCR), diethylene glycol monobutyl ether, N-cyclohexylpyrrolidone, etc., but there are still many problems in the promotion and application and economics. The newly developed 85% diethylene ethylene The mixture of alcohol and 10% N-cyclohexylpyrrolidone is a good substitute, the price is also moderate, the commodity is Swelling agent G, but the recovery of the mixed solvent needs to be solved; although the flame retardant finishing agent has developed some halogen-free New varieties such as bicyclic caged phosphate derivative flame retardants, organic boron flame retardants, organic compounds and inorganic nitrogen salt composites, alkyl phosphate nitrogen derivative flame retardants, etc., but the current mainstream varieties on the market Even the newly developed varieties are still organic halides, which contain adsorbable organic halides. It can be seen that in order to ensure the safety of textiles, of the six basic safety requirements for textile additives, there are currently no EH and no AOX still exist Issues, which is what today's hot issues of concern to public safety in textile auxiliaries.
