A non-water dyeing method of greige cotton fabric without pretreatment

Abstract

The application discloses a kind of green cotton fabric non-pretreatment non-water dyeing method, including the following steps: 1) inorganic alkali, penetrant and water are mixed uniformly, and alkali solution is prepared;Alkali solution is used to carry out infiltration treatment to green cotton fabric, and the green cotton fabric after infiltration treatment is carried out drying treatment;2) active dye and polar solvent are mixed uniformly, and first solution is prepared;Auxiliary agent and non-polar solvent are mixed uniformly, and second solution is prepared;First solution and second solution are mixed uniformly, and dye bath is prepared;Dye bath is used to carry out dyeing treatment to the green cotton fabric after drying treatment obtained in step 1), and non-water dyed green cotton fabric is obtained.The non-water dyeing method provided by the application realizes the non-water dyeing of green cotton fabric, realizes the process of non-pretreatment;Dyeing product is even in color, and color light is natural, and fixing rate is as high as 97% or more, and the natural softness, smoothness, water repellency and hand feeling of cotton fabric are kept, and hand feeling is significantly better than ordinary pretreated fabric.

Description

Technical Field

[0001] This invention relates to the field of dyeing and finishing technology. More specifically, it relates to a non-aqueous dyeing method for raw cotton fabrics that requires no pretreatment. Background Technology

[0002] As a major producer and processor of cotton textiles, China generates millions of tons of cotton fabrics annually that require pretreatment, dyeing, and other processing. Traditional cotton fabric production processes consume significant amounts of water, especially pretreatment and dyeing, which not only consume large quantities of water but also produce wastewater with high COD and color, posing significant challenges for wastewater treatment and representing a major obstacle to the development of the dyeing and printing industry.

[0003] With the increasing scarcity of water resources and the gradual strengthening of environmental regulations and awareness both domestically and internationally, reducing dyeing wastewater and developing non-aqueous dyeing media has become a major direction for the transformation of the textile industry. Among these, critical carbon dioxide dyeing and non-aqueous solvent dyeing are two main directions in non-aqueous dyeing media. While critical carbon dioxide dyeing has been extensively researched both domestically and internationally, its application is limited due to significant limitations on the dyes and fibers used, as well as the need for ultra-high pressure in the dyeing equipment. This has resulted in slow industrialization. Non-aqueous solvent dyeing primarily refers to using solvents instead of water as the dyeing medium, avoiding dye hydrolysis during the dyeing process, thereby achieving high dye utilization and high colorfastness of the fabric. Since no water is used during the dyeing process, and all non-aqueous solvents are recycled and reused after dyeing, no dyeing wastewater or waste liquid is generated.

[0004] The existing polar / non-polar binary non-aqueous dyeing process is as follows: pretreatment - alkali treatment - drying - dye bath preparation - dyeing. In this process, the yarn needs to undergo pretreatment, which consumes 24-40 tons of water per ton of cotton fabric. Before conventional water dyeing, cotton fabrics need to be pretreated to remove cotton wax, grease, pectin, etc., from the surface of the fibers to improve the hydrophilicity of the cotton fibers, thereby achieving dye diffusion and even dyeing.

[0005] After achieving anhydrous dyeing processes, developing water-saving or waterless pretreatment technologies or developing pretreatment-free dyeing processes has become a major challenge in non-aqueous dyeing. The solutions directly relate to the feasibility of industrialization and promotion of this technology and the economic interests of enterprises.

[0006] Therefore, the present invention provides a non-water dyeing method for raw cotton fabrics without pretreatment, solving the related dyeing technology problems of raw cotton fabrics without pretreatment in non-water dyeing. Summary of the Invention

[0007] One object of the present invention is to provide a non-water dyeing method for raw cotton fabrics that does not require pretreatment.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] A non-aqueous dyeing method for raw cotton fabric without pretreatment includes the following steps:

[0010] 1) Mix inorganic alkali, penetrant and water to prepare alkali solution; use alkali solution to impregnate the raw cotton fabric, and then dry the impregnated raw cotton fabric.

[0011] 2) Mix the reactive dye and polar solvent to obtain a first solution; mix the dyeing aid and non-polar solvent to obtain a second solution; mix the first solution and the second solution to obtain a dye bath; use the dye bath to dye the dried cotton fabric obtained in step 1) to obtain a non-water-dyed cotton fabric.

[0012] Preferably, the untreated untreated cotton fabric used in step 1) to impregnate the untreated cotton fabric with an alkaline solution is an untreated untreated cotton fabric, specifically including untreated cotton, untreated yarn, untreated fabric and other forms of untreated untreated cotton fabric.

[0013] Preferably, the inorganic base in step 1) includes one or more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and sodium bicarbonate.

[0014] Preferably, the penetrant in step 1) includes one or more of anionic penetrants, cationic penetrants, and nonionic penetrants; wherein, anionic penetrants include, for example, Xianqiao FKS or Demei Chemical DM-1573, and nonionic penetrants include, for example, Demei Chemical DM1133 or Keke Chemical EPDC.

[0015] Preferably, the concentration of inorganic alkali in the alkaline solution in step 1) is 5 g / L to 50 g / L.

[0016] Preferably, the concentration of the penetrant in the alkaline solution in step 1) is 0.1 g / L to 10 g / L.

[0017] Preferably, the impregnation treatment in step 1) includes one or more of soaking, spraying, rolling and pump circulation.

[0018] Preferably, the temperature of the immersion treatment in step 1) is 0℃~100℃.

[0019] Preferably, the liquid retention rate of the raw cotton fabric after the impregnation treatment in step 1) is 50% to 120%.

[0020] Preferably, the drying temperature in step 1) is 80℃~100℃, and the drying time is 1 minute~10 minutes.

[0021] Preferably, the unsuitable solvent for the reactive dye in step 2) includes one or more of the following: alkanes, chlorinated hydrocarbons, aromatics, ketones, silanes, esters, and ethers.

[0022] Preferably, the reactive dye in step 2) is a vinyl sulfone reactive dye, a triazine reactive dye, or a pyrimidine reactive dye; wherein, vinyl sulfone reactive dyes include Huntsman SE Red or SE DEEP Blue, triazine reactive dyes include Sumitomo Chemical Yellow 3RF, and pyrimidine reactive dyes include DyStar Red E-6BA.

[0023] Preferably, the polar solvent in step 2) includes one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, ionic liquids, and alcohol ether solvents.

[0024] Preferably, in step 2), the concentration of the reactive dye in the first solution is 0.1 g / L to 50 g / L.

[0025] Preferably, the dyeing aid in step 2) includes one or more of the following: higher fatty acid esters, C8-C18 carbon chain quaternary ammonium salts, and C20-C28 straight-chain alkanes.

[0026] Preferably, the nonpolar solvent in step 2) includes one or more of dimethyl carbonate, pentapentaerythrane, n-heptane, chloroform, vinyl chloride, decamethylcyclopentasiloxane, and petroleum ether.

[0027] Preferably, in step 2), the concentration of the dyeing agent in the second solution is 0.1 g / L to 15 g / L.

[0028] Preferably, the volume ratio of the first solution and the second solution in the dye bath in step 2) is 1:6 to 10.

[0029] Preferably, the ratio of the dye bath to the raw cotton fabric in step 2) is 5L to 50L: 1Kg.

[0030] Preferably, the staining process in step 2) includes heating to 80°C to 100°C at a heating rate of 0.1°C / min to 5°C / min, and then staining for 30 to 120 minutes.

[0031] Preferably, after the staining treatment in step 2) is completed, a step of recovering the solvent is also included.

[0032] In addition, unless otherwise specified, any range described in this invention includes the endpoint, any value between the endpoints, and any subrange consisting of the endpoint or any value between the endpoints.

[0033] The beneficial effects of this invention are as follows:

[0034] (1) The non-water dyeing method provided by the present invention achieves non-water dyeing of raw cotton fabrics without pretreatment process; the dyed finished product has uniform color and natural color, with a color fixation rate of over 97%, and retains the natural softness and smoothness of cotton fabrics, and its water repellency and hand feel are significantly better than those of fabrics after ordinary pretreatment.

[0035] (2) The non-aqueous solvent combination used in the non-aqueous dyeing method provided by the present invention has a strong penetrating ability to cotton wax and grease on the surface of cotton fibers, so there is no need to pre-treat the raw cotton before dyeing to remove impurities such as cotton wax; the pre-treatment process is eliminated, saving the chemicals, water and electricity consumed in the pre-treatment; the alkaline solution used can be recycled and no wastewater is generated.

[0036] (3) The non-aqueous dyeing method provided by the present invention retains the cotton wax and oil on the cotton fiber without pretreatment. It has higher compatibility with the solvent medium of non-aqueous dyeing, which allows the solvent to carry the dye into the fiber deeper, making the fabric more uniform in color and more saturated and natural in color.

[0037] (4) The non-water dyeing method provided by the present invention eliminates the need for pretreatment and retains the cotton wax on the cotton fibers, which can save the softening and winding waxing processes after dyeing and drying the yarn; the preservation of the cotton wax on the cotton fibers themselves also preserves the natural softness and smooth feel of the cotton fabric; compared with the fabric performance obtained by applying softener after pretreatment in the prior art, it has higher durability and a more natural feel.

[0038] (5) The method of the present invention is simple and easy to operate, with low process difficulty, environmental protection and energy saving, and easy to industrialize and promote, and has considerable economic advantages. Detailed Implementation

[0039] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments, further clarifies the invention. Those skilled in the art should understand that the specific descriptions below are illustrative rather than restrictive, and should not be construed as limiting the scope of protection of the present invention.

[0040] In this invention, the preparation methods are all conventional unless otherwise specified; the raw materials used can be obtained from publicly available commercial sources unless otherwise specified.

[0041] Example 1

[0042] This embodiment provides a non-water dyeing method for raw cotton fabrics that does not require pretreatment, including the following steps:

[0043] 1) Weigh 15g of potassium hydroxide and 0.5g of penetrant EPDC and dissolve them in 1L of water. Stir well to prepare an alkaline solution. Add 50g of knitted fabric to the alkaline solution for immersion treatment. Soak at room temperature for 30min, then immerse and rub twice to control the liquid retention rate of the knitted fabric after immersion treatment to 100%. Dry the knitted fabric after immersion treatment at 100℃.

[0044] 2) Dissolve 1.5g of reactive dye SE Red in 100mL of dimethylformamide as a polar solvent to prepare the first solution;

[0045] Prepare n-octane containing 0.5 g / L of higher fatty acid esters as a second solution;

[0046] Prepare a dye bath by mixing the first solution and the second solution at a volume ratio of 1:10.

[0047] The dried knitted fabric obtained in step 1) was dyed using a dye bath. The temperature was increased to 80℃ at 1℃ / min and dyed for 120 minutes to obtain a non-water-dyed knitted fabric. The non-water-dyed knitted fabric had uniform color, a K / S value of 24, and a color fixation rate of 98.3%. The color difference test results are shown in Table 1.

[0048] Example 2

[0049] This embodiment provides a non-water dyeing method for raw cotton fabrics that does not require pretreatment, including the following steps:

[0050] 1) Weigh 60g of sodium carbonate and 0.5g of penetrant FKS and dissolve them in 1L of water. Stir well to prepare an alkaline solution. Add 50g of knitted fabric to the alkaline solution for immersion treatment. Soak at 60℃ for 30min, then perform three dips and three squeezes to control the liquid retention rate of the knitted fabric after immersion treatment to 100%. Dry the knitted fabric after immersion treatment at 100℃.

[0051] 2) Dissolve 1.5g of reactive dye SE DEEP Blue in 200mL of dimethyl sulfoxide as a polar solvent to prepare the first solution;

[0052] A second solution containing 0.5 g / L dodecyltrimethylammonium chloride was prepared using decamethylcyclopentasiloxane.

[0053] Prepare a dye bath by mixing the first solution and the second solution at a volume ratio of 1:8.

[0054] The knitted fabric obtained after drying in step 1) was dyed using a dye bath. The temperature was increased to 100℃ at a rate of 1℃ / min and dyed for 45 minutes to obtain a non-water-dyed knitted fabric. The non-water-dyed knitted fabric had uniform color, a K / S value of 25.8, and a color fixation rate of 97.5%. The color difference test results are shown in Table 1.

[0055] Example 3

[0056] This embodiment provides a non-water dyeing method for raw cotton fabrics that does not require pretreatment, including the following steps:

[0057] 1) Weigh 100g of sodium hydroxide and 5g of penetrant DM1133 and dissolve them in 12L of water. Stir well to prepare an alkaline solution. Add 3Kg of raw yarn to the alkaline solution for impregnation. After 60min of unidirectional outward flow in a yarn dyeing machine at 40℃, centrifuge to dehydrate and control the liquid content of the impregnated raw yarn to 60%. Dry the impregnated raw yarn at 90℃.

[0058] 2) Dissolve 40g of reactive dye SE Red in 18L of dimethyl sulfoxide as a polar solvent to prepare the first solution;

[0059] Prepare n-octane containing 0.5 g / L hexadecane as a second solution;

[0060] Prepare a dye bath by mixing the first solution and the second solution at a volume ratio of 1:8.

[0061] The dried yarn obtained in step 1) was dyed using a dye bath. The temperature was increased to 100℃ at a rate of 1℃ / min, and the dyeing was carried out for 60 minutes to obtain non-aqueous dyed yarn. The non-aqueous dyed yarn had uniform color, a K / S value of 18.3, a color fixation rate of 97.2%, and a yarn difference of 0.36 between the inner and outer layers of the yarn. The color difference test results are shown in Table 1.

[0062] Example 4

[0063] This embodiment provides a non-water dyeing method for raw cotton fabrics that does not require pretreatment, including the following steps:

[0064] 1) Weigh 20g of sodium hydroxide, 200g of ammonium carbonate, and 5g of penetrant FKS and dissolve them in 10L of water. Stir well to prepare an alkaline solution. Add 2kg of raw cotton to the alkaline solution for impregnation. After 45min of unidirectional outward flow in a cotton dyeing machine at 70℃, centrifuge to dehydrate and control the liquid content of the impregnated raw cotton to 60%. Dry the impregnated raw cotton at 90℃.

[0065] 2) Dissolve 60g of reactive dye Blue SP-G in 5L of dimethylacetamide as a polar solvent to prepare the first solution;

[0066] Prepare tetrachloroethylene containing 0.5 g / L hexadecane as a second solution;

[0067] Prepare a dye bath by mixing the first solution and the second solution at a volume ratio of 1:6;

[0068] The dried cotton obtained in step 1) was dyed using a dye bath. The temperature was increased to 90℃ at 1℃ / min and dyed for 60 minutes to obtain non-aqueous dyed cotton. The non-aqueous dyed cotton had uniform color, a K / S value of 39.4, and a color fixation rate of 97.3%. The color difference test results are shown in Table 1.

[0069] Comparative Example 1

[0070] This comparative example provides a non-water-based dyeing method for raw cotton fabrics that requires no pretreatment, including the following steps:

[0071] 1) Weigh 60g of sodium carbonate and 0.5g of penetrant EPDC and dissolve them in 1L of water. Stir well to prepare an alkaline solution. Add 50g of knitted fabric to the alkaline solution for immersion treatment. Soak at 60℃ for 30min, then perform three dips and three squeezes to control the liquid retention rate of the knitted fabric after immersion treatment to 100%. Dry the knitted fabric after immersion treatment at 100℃.

[0072] 2) Dissolve 1.5g of reactive dye SE Red and 10g of sodium sulfate in 500mL of pure water to prepare a dye bath;

[0073] The dried knitted fabric obtained in step 1) was added to the dye bath, and the temperature was increased by 1℃ / min for dyeing. When the temperature reached 60℃, 5g of soda ash was added in 3 steps, and the temperature was held for 1h. After washing, the knitted fabric dyed in water medium was obtained. The surface of the knitted fabric dyed in water medium had obvious color spots, the K / S value was 18.92, the fixation rate was 71.6%, and the color difference test results are shown in Table 1.

[0074] Table 1 Color difference test results

[0075] K / S difference in different areas of the fabric 3.3 0.72 0.57 0.66 0.92 Color difference in different areas of the fabric 1.40 0.58 0.43 0.48 0.68

[0076] The above test results demonstrate that the non-water-based dyeing method for cotton fabrics without pretreatment of the present invention has significant advantages over water-based methods in terms of even dyeing and penetration of raw cotton fabrics.

[0077] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A non-aqueous dyeing method for raw cotton fabrics without pretreatment, characterized in that, Includes the following steps: 1) Weigh 60g of sodium carbonate and 0.5g of penetrant FKS and dissolve them in 1L of water, stir well to prepare an alkaline solution; add 50g of knitted fabric to the alkaline solution for immersion treatment, soak at 60℃ for 30min, then perform three dips and three squeezes, controlling the liquid retention rate of the immersion-treated knitted fabric to 100%, and then dry the immersion-treated knitted fabric; wherein, the knitted fabric is an untreated knitted fabric, and the pretreatment includes the removal of cotton wax. 2) Dissolve 1.5g of reactive dye SE DEEP Blue in 200mL of dimethyl sulfoxide as a polar solvent to prepare the first solution; A second solution containing 0.5 g / L dodecyltrimethylammonium chloride was prepared using decamethylcyclopentasiloxane. Prepare a dye bath by mixing the first solution and the second solution at a volume ratio of 1:

8. The dried knitted fabric obtained in step 1) was dyed using a dye bath. The temperature was increased to 100℃ at 1℃ / min and dyed for 45 minutes to obtain a non-water-dyed knitted fabric.

2. The non-aqueous dyeing method for raw cotton fabrics without pretreatment according to claim 1, characterized in that, The drying temperature in step 1) is 80℃~100℃, and the drying time is 1 minute~10 minutes.