A plant indigo dip dyeing process for ready-made garments and the obtained indigo-dyed garments

Abstract

The present invention provides a plant indigo exhaust dyeing process for garments and the resulting indigo-dyed garments. The process comprises placing garments to be dyed in a non-air-insulated dyeing machine and adding water for infiltration; pumping a mixed solution of liquid caustic soda and sodium sulfate into the dyeing machine and operating the dyeing machine; mixing a plant indigo dye solution and a sodium sulfate solution and adding the mixture into the dyeing machine to dye the garments; pumping the mixed solution of liquid caustic soda and sodium sulfate into the dyeing machine and continuing to dye the garments; subjecting the dyed garments to oxidative water washing, dehydration, drying, ozone treatment, and water softening treatment to obtain indigo-dyed garments. The process provided by the present invention has the advantages of simple process, short dyeing time, convenient operation, re-dyeing and reworkability, and good stability. The indigo-dyed garments obtained by the process have unique style, uniform color, bright color, fresh and natural style, high color fastness, and meet the first-class plant dye standard, meeting subsequent wearing requirements.

Description

Technical Field

[0001] The invention relates to a plant indigo dip dyeing process for ready-made clothing and the obtained indigo-dyed clothing, belonging to the technical field of natural dye dyeing. Background Art

[0002] Indigo is an ancient plant-based dye, primarily extracted from plants such as magnolia, polygonum, amaranth, and woad. Different indigo plants contain varying amounts of indigo and vary in their growing conditions. Therefore, compared to synthetic indigo, plant-based indigo suffers from unstable sourcing, large batch variations, and difficulty in achieving darker colors. Like many plant-based dyes, plant-based indigo suffers from poor dyeing stability, colorfastness, and industrial production challenges. However, in today's climate of environmental protection and low carbon emissions, people are increasingly prioritizing sustainable development and embracing nature and biodegradable products. Because plant-based dyes are naturally derived, biodegradable, and environmentally friendly, and offer a fresh, natural aesthetic with pure, soft colors, they are making a comeback and are gaining popularity.

[0003] As a vat dye, indigo dyeing requires two processes: reduction and oxidation. First, it is reduced to a leuco form, which is soluble and diffuses into the fiber in the dye bath. It is then oxidized by air or hydrogen peroxide into water-insoluble solid particles that adhere to the fiber. Because leuco indigo is prone to uneven oxidation by air after being applied to garments in the dye bath, resulting in uneven dyeing, indigo garments currently require dyeing in an airtight environment filled with nitrogen or other inert gases. This results in small industrial production volumes and high costs.

[0004] Natural cellulose fiber fabrics offer excellent properties for environmental friendliness, sustainable development, comfort, and breathability. However, cellulose fibers possess a surface potential in an alkaline bath, creating a charge repulsion with the indigo leuco anion, hindering dye diffusion into the fiber and resulting in low dye uptake. Therefore, conventional dyeing processes for indigo-dyed cellulose fiber fabrics rely on stacking dyeing cycles to achieve a deep and even dyeing depth, typically requiring 5-6 dyeing cycles to achieve a medium-dark color. However, excessive dyeing cycles increases dyeing time and costs, making them unsuitable for large-scale industrial production.

[0005] Therefore, providing a novel plant indigo dyeing (one-time dyeing) process for garments and the resulting indigo-dyed garments has become a technical problem that needs to be urgently solved in the art. Summary of the Invention

[0006] To address the aforementioned shortcomings and deficiencies, one object of the present invention is to provide a process for plant-based indigo exhaust dyeing of garments. This process achieves uniform indigo exhaust dyeing of garments in conventional environments, breaking the barrier of prior art that requires nitrogen or other inert gases to isolate the garment from the air, significantly accelerating industrial production.

[0007] Another object of the present invention is to provide an indigo-dyed garment, which is produced by the above-mentioned garment plant indigo exhaust dyeing process.

[0008] In order to achieve the above objectives, in one aspect, the present invention provides a plant indigo exhaust dyeing process for garments, wherein the plant indigo exhaust dyeing process for garments comprises:

[0009] (1) Place the garment to be dyed into a non-air-tightened dyeing machine and add water for soaking;

[0010] (2) pumping a mixed solution of liquid caustic soda and sodium hyposulfite into a dyeing machine and operating the dyeing machine;

[0011] (3) mixing the plant indigo dye solution and the sodium sulfate solution and adding the mixture into a dyeing machine to dye the garment;

[0012] (4) Pumping the mixed solution of liquid alkali and hydrosulfite into the dyeing machine to continue dyeing the garment;

[0013] (5) The dyed garments are subjected to oxidative washing, dehydration, drying, ozone treatment and water softening treatment to obtain indigo dyed garments.

[0014] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, the fabric of the garments includes natural fiber fabrics, chemical fiber fabrics, or blended fabrics of natural fibers and chemical fibers.

[0015] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, the natural fibers include one or more of cotton, linen, silk and wool.

[0016] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, the chemical fiber includes one or more of acrylic, viscose, nylon and polyester.

[0017] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, wherein, in step (1), the bath ratio of the garment to water is 1:10-50.

[0018] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, the dyeing machine rotates 5-20 times and then stops for 1-10 seconds, then reverses for 5-20 times and then stops for 1-10 seconds, and rotates a total of 10-50 times within 1 minute. The dyeing operation time of the dyeing machine, that is, the time from the time the dye is drawn in to the time the dye dyes the garment in the dyeing machine, is 3-30 minutes, and the total operation time of the dyeing machine is 30-60 minutes, which includes all feeding and operation time from the time the garment is fed in.

[0019] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, in step (2), the concentration of liquid caustic soda and sodium hydrosulfite in the mixed solution is 0.2-10 g / L and 0.1-10 g / L, respectively, based on the total volume of the mixed solution.

[0020] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, the running time of the dyeing machine in step (2) is 2-30 minutes, preferably 2-20 minutes.

[0021] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, in step (3), the substances are weighed in sequence according to a mass concentration of plant indigo of 5-80 g / L and a mass concentration ratio of plant indigo, hydrosulfite, and liquid caustic soda of 1:1-40:1-50, each substance is added to cold water and mixed uniformly, and then a defoaming agent is added to the obtained dye liquor, and the mixture is mixed uniformly to obtain a plant indigo dye liquor;

[0022] Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of glauber salt is 5-80 g / L, and the mass concentration of the defoaming agent is 0.1-5 g / L.

[0023] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, the following steps are performed: weighing the substances in sequence according to a mass concentration of 10-50 g / L of plant indigo and a mass concentration ratio of 1:1-30:1-40 of plant indigo, adding the substances to cold water and mixing them uniformly; then adding a defoaming agent to the resulting dye liquor, and mixing them uniformly to obtain a plant indigo dye liquor;

[0024] Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of sodium sulfate is 10-60g / L.

[0025] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, the pH value of the plant indigo dye solution is in the range of 11-13.

[0026] In the above-described plant indigo exhaust dyeing process for garments of the present invention, 5-80 g / L (preferably 10-50 g / L) refers to the concentration of plant indigo when preparing the plant indigo dye liquor outside the dyeing machine. In the dyeing machine, the indigo concentration after dilution can be as low as 0.1 g / L, preferably not less than 1 g / L. The corresponding potential value of the plant indigo dye liquor ranges from -760 mV to -1000 mV. When the diluted indigo concentration is lower than 1 g / L, the potential of the plant indigo leuco solution dye liquor can be changed by adjusting the mass concentration ratio of plant indigo, hydrosulfite and liquid caustic soda. The preferred concentration ratio range of indigo: hydrosulfite: liquid caustic soda is 1:(1-20):(1-30). As shown in Table 1, the potential can reach -901.8 mV, so as to achieve a bright and uniform color effect for the dyed garments. When the diluted indigo concentration is lower than 1 g / L, if the mass concentration ratio of plant indigo, hydrosulfite and liquid caustic soda is not adjusted, the potential of the plant indigo leuco solution dye liquor is not within the above-defined range of -760 mV to -1000 mV, thereby failing to achieve a bright and uniform color effect for the dyed garments.

[0027] In the above-mentioned plant indigo exhaust dyeing process for ready-made garments provided by the present invention, the total volume of the liquid in the dyeing machine during dyeing includes: the total volume of the water added in advance according to the calculated bath ratio before dyeing, the mixed solution of liquid alkali and sodium sulfate during idling, the mixed solution of indigo dye solution and sodium sulfate solution pumped into the dyeing machine, and the mixed solution of liquid alkali and sodium sulfate used for secondary reduction.

[0028] In the present invention, when sodium sulfate is externalized in the dyeing machine and the sodium sulfate solution is prepared, the saturation of the solution cannot exceed 30%, that is, 1 mL of water contains 0.3 g of sodium sulfate. After the sodium sulfate solution is injected into the dyeing machine, it will be diluted. The concentration in the machine after dilution is the mass concentration of sodium sulfate calculated based on the total volume of the liquid in the dyeing machine during dyeing.

[0029] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, in step (3), the plant indigo dye solution and the sodium sulfate solution are mixed and then added to the dyeing machine, wherein the feeding time is 2-20 minutes, and after all the mixed solution is added to the dyeing machine, the dyeing machine is continued to run for 2-30 minutes to dye the garment, wherein the dyeing temperature is 30-60°C.

[0030] Since a large amount of foam is generated when dyeing garments with plant indigo, the water inlet sensor of the dyeing machine after drainage will become insensitive, resulting in the inability to take in water and the machine shutting down. Adding a defoaming agent can avoid the shutdown situation. The defoaming agent used in the present invention can be a conventional defoaming agent, such as an alkali-resistant defoaming agent and a water treatment defoaming agent. In some embodiments of the present invention, the alkali-resistant defoaming agent can be a defoaming agent model 3310 produced by Henan Bozhiyuan Water Purification Materials Co., Ltd., the main component of which is a polyether substance. The water treatment defoaming agent can be, for example, a defoaming agent model DJ-1244 produced by Guangzhou Zhongwan New Materials Co., Ltd., the main component of which is silicone.

[0031] In the above-mentioned plant indigo exhaust dyeing process for garments provided by the present invention, in step (3), the plant indigo leuco dye in the dyeing machine is oxidized in only about 3 minutes under the condition of continuous rotation. When the color of the plant indigo dye solution in the dyeing machine changes from yellow-green to blue, it is confirmed that most of the plant indigo leuco dye has been oxidized. At this time, a mixed solution of liquid caustic soda and sodium hyposulfite can be pumped into the dyeing machine to achieve secondary reduction of the indigo dye solution and continue dyeing the garment.

[0032] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, in step (4), the concentration of liquid caustic soda and sodium hydrosulfite in the mixed solution is 0.1-2 g / L and 0.5-5 g / L, respectively, based on the total volume of the mixed solution.

[0033] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, in step (4), the dyeing time is 1-20 minutes.

[0034] Since the dyeing machine used in the present invention is a non-air-insulated dyeing machine, most of the plant indigo leuco body will be oxidized after dyeing for a period of time in step (3), and the mixed solution of liquid alkali and hydrosulfite added in step (4) can secondary reduce the oxidized plant indigo leuco body, maintain the reduction potential in the dyeing solution, and prolong the diffusion dyeing time of the indigo dye, thereby prolonging the dyeing time and ensuring that the finished garment is fully dyed.

[0035] As a specific embodiment of the above-mentioned garment plant indigo exhaust dyeing process of the present invention, the bath ratio of the dyeing process in step (3) and step (4) is controlled at 1:10-1:50, preferably 1:20.

[0036] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, in step (5), the bath ratio of the oxidative washing process is 1:10-50, the amount of hydrogen peroxide used is 0.1-10 g / L based on the total volume of the liquid during the oxidative washing, the oxidative washing time is 1-30 min, and the number of oxidative washings is 1-10 times.

[0037] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, in step (5), the dehydration speed is 100-500 r / min.

[0038] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, in step (5), the drying temperature is 50-90°C.

[0039] As a specific embodiment of the above-described plant indigo exhaust dyeing process for garments of the present invention, in step (5), the ozone concentration is 1-20% by volume, based on the total volume of the ozone generator used for ozone treatment, and the treatment time is 5-50 minutes. The ozone treatment can remove loose color from the surface of the garment, thereby effectively improving the color fastness of the indigo garment.

[0040] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, in step (5), the amount of softener used in the wash water over-softening treatment process is 0.5-5 g / L based on the total volume of the liquid during the wash water over-softening treatment, the bath ratio is 1:10-50, and the wash water over-softening treatment time is 5-30 min.

[0041] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, the softener is an antioxidant softener.

[0042] The antioxidant softener used in the present invention is a conventional antioxidant softener. In some embodiments of the present invention, the antioxidant softener can be, for example, an antioxidant softening oil, specifically HS-1510 anti-yellowing softening oil produced by Zhongshan Hongsheng Biotechnology Co., Ltd.; the antioxidant softener can also be SS-29 non-silicone softener produced by Dongguan Guiruan Biotechnology Co., Ltd.

[0043] As a specific embodiment of the above-mentioned plant indigo exhaust dyeing process for garments of the present invention, the garments are cotton and linen garments.

[0044] On the other hand, the present invention also provides an indigo-dyed garment, wherein the indigo-dyed garment is produced by the above-mentioned garment plant indigo exhaust dyeing process.

[0045] Compared with current dyeing technologies, the plant indigo dyeing process for garments provided by the present invention can achieve the following beneficial technical effects:

[0046] 1) Since the present invention uses a non-air-isolated dyeing machine, a mixed solution of liquid caustic soda and hydrosulfite is first pumped into the dyeing machine before dyeing and the dyeing machine is idling to eliminate some of the oxygen in the dyeing machine. At the appropriate time point in the dyeing process, the mixed solution of caustic soda and hydrosulfite is continued to be added to achieve secondary reduction of the indigo dye liquor, so that the dyed fabric can achieve a uniform and continuous dyeing effect at a suitable bath ratio and rotation speed. Therefore, the present invention uses an ordinary washing machine, which is equivalent to a dyeing machine that can achieve uniform indigo coloring of finished garments in a conventional aerobic environment, breaking the barrier of the prior art that dyeing must be carried out in an environment isolated from the air by nitrogen or other inert gases to achieve uniform dyeing. In the case of no machine restrictions, the output is increased while the dyeing cost is greatly reduced, and large-scale industrial production of indigo garment immersion dyeing can be specifically achieved.

[0047] 2) Due to the particularity that the indigo dye solution is continuously oxidized by the air in the dyeing machine, the plant indigo dyeing process for ready-made garments provided by the present invention directly mixes the prepared sodium sulfate solution with the plant indigo dye solution. Before the plant indigo leuco body is oxidized, the charge repulsion between the fiber and the plant indigo leuco body anion in the dye bath is eliminated, so that the dye and the fiber interface are in close contact, the dyeing percentage is increased, and the fabric is dyed to a medium-dark color within a limited dyeing time. This greatly reduces the dyeing time, saves dyeing costs, and is more conducive to industrial production.

[0048] 3) In summary, the plant indigo dyeing process for garments provided by the present invention has the advantages of simple process, short dyeing time, convenient operation, re-dyeing and repairability, and good stability. The indigo-dyed garments obtained by the process have a unique style, uniform color, bright color, fresh and natural style, high color fastness, and meet the first-class plant dye standards, meeting subsequent clothing requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0050] Figure 1 This is a rendering of the partial appearance of the indigo-dyed garment produced in Example 1 of the present invention.

[0051] Figure 2 This is a rendering of the partial appearance of the indigo-dyed garment prepared in Comparative Example 1.

[0052] Figure 3 This is a rendering of the partial appearance of the indigo-dyed garment prepared in Comparative Example 2.

[0053] Figure 4 This is a rendering of the partial appearance of the indigo-dyed garment prepared in Comparative Example 3.

[0054] Figure 5 This is a partial appearance rendering of the indigo-dyed garment prepared in Comparative Example 4.

[0055] Figure 6 This is a partial appearance rendering of the indigo-dyed garment prepared in Example 4.

[0056] Figure 7 This is a partial appearance rendering of the indigo-dyed garment prepared in Example 5.

[0057] Figure 8 This is a partial appearance rendering of the indigo-dyed garment prepared in Example 6.

[0058] Figure 9 This is a partial appearance rendering of the indigo-dyed garment prepared in Example 7.

[0059] Figure 10 This is a rendering of the partial appearance of the indigo-dyed garment prepared in Example 8.

[0060] Figure 11 This is a rendering of the partial appearance of the indigo-dyed garment prepared in Example 9. DETAILED DESCRIPTION

[0061] It should be noted that the term "comprise" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or apparatus.

[0062] The "range" disclosed in the present invention is given in the form of a lower limit and an upper limit. It can be one or more lower limits, and one or more upper limits respectively. A given range is defined by selecting a lower limit and an upper limit. The selected lower limit and upper limit define the boundaries of a particular range. All ranges defined in this way are combinable, i.e., any lower limit can be combined with any upper limit to form a range. For example, a range of 60-120 and 80-110 is listed for a particular parameter, and it is understood that a range of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​listed are 1 and 2, and the maximum range values ​​listed are 3, 4, and 5, then the following ranges can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5.

[0063] In the present invention, unless otherwise specified, the numerical range "ab" is an abbreviation for any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" are listed in this invention, and "0-5" is merely an abbreviation for these numerical combinations.

[0064] In the present invention, unless otherwise specified, all embodiments and preferred embodiments mentioned in the present invention can be combined with each other to form a new technical solution.

[0065] In the present invention, unless otherwise specified, all technical features and preferred features mentioned in the present invention can be combined with each other to form a new technical solution.

[0066] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the attached table, drawings and examples. The following embodiments are some embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified in the examples, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0067] Example 1

[0068] This embodiment provides a plant indigo exhaust dyeing process for garments, wherein the process comprises the following specific steps:

[0069] (1) Weigh 3 kg of knitted pure cotton round-neck T-shirts and place them in a garment dyeing machine, add water at a bath ratio of 1:10 and soak them. The speed of the dyeing machine is set to 5-10-50, that is, the dyeing machine rotates 5 times and then stops for 10 seconds, then reverses 5 times and then stops for 10 seconds, and rotates a total of 50 times in 1 minute.

[0070] (2) A mixed solution of 0.1 g / L sodium hydroxide and 0.2 g / L caustic soda was pumped into the dyeing machine and run for 10 min; the concentrations of caustic soda and sodium hydroxide were calculated based on the total volume of the mixed solution.

[0071] (3) Prepare 12 liters of plant indigo dye solution, weigh each substance in sequence according to the mass concentration ratio of plant indigo, sodium hydroxide and liquid alkali (sodium hydroxide mass concentration is 50%, the balance is water) of 1:4:2, add liquid alkali, plant indigo and sodium hydroxide into cold water in sequence (the amount of water used for the dissolution of plant indigo and sodium hydroxide is 12 L, and this 12 L of water includes the water in the liquid alkali, and the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25 g / L) and mix them evenly, add defoaming agent to the obtained dye solution after dissolution, stir and mix evenly to obtain plant indigo dye solution, and the indigo concentration after dilution is 5 g / L;

[0072] Weighing sodium sulfate and dissolving it in cold water and then mixing it evenly with the plant indigo dye solution to obtain a mixed solution of plant indigo leuco body and sodium sulfate, adding the mixed solution into a dyeing machine to dye the garment, the feeding time is 3 minutes, the bath ratio of the dyeing process is controlled at 1:20, the dyeing temperature is 30°C, and the dyeing time is 10 minutes;

[0073] Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of alum is 10 g / L, and the mass concentration of the defoaming agent is 5 g / L. The defoaming agent is model 3310 produced by Henan Bozhiyuan Water Purification Materials Co., Ltd., and its main component is polyether substances.

[0074] (4) A mixed solution of 3 g / L sodium hypochlorite and 5 g / L liquid alkali was pumped into the dyeing machine and dyeing was continued for 10 minutes. The concentrations of liquid alkali and sodium hypochlorite were calculated based on the total volume of the mixed solution, and the bath ratio of the dyeing process was controlled at 1:20.

[0075] (5) The dyed garments are sequentially subjected to oxidation washing, dehydration, drying, ozone treatment and water softening treatment;

[0076] The bath ratio of the oxidation water washing process is 1:50, the amount of hydrogen peroxide used is 5 g / L based on the total volume of the liquid during the oxidation water washing, and the number of oxidation water washings is 2 times;

[0077] The dehydration speed is 500r / min;

[0078] The drying temperature is 90℃;

[0079] Based on the total volume of the ozone machine used for ozone treatment, the ozone concentration is 1v%, and the treatment time is 5min;

[0080] Based on the total volume of the liquid during the water softening treatment, the amount of softener used in the water softening treatment process is 0.5 g / L, the bath ratio is 1:10, and the water softening treatment time is 5 minutes. The softener is HS-1510 anti-yellow softening oil produced by Zhongshan Hongsheng Biotechnology Co., Ltd.

[0081] After washing and softening, the indigo-dyed garment is obtained, and its local appearance effect is as follows Figure 1 shown.

[0082] Example 2

[0083] This embodiment provides a plant indigo exhaust dyeing process for garments, wherein the process comprises the following specific steps:

[0084] (1) Weigh 3 kg of woven linen shirts and soak them in water at a bath ratio of 1:10 in a garment dyeing machine. The speed of the dyeing machine is set to 5-10-50, that is, the dyeing machine rotates 5 times and then stops for 10 seconds, then reverses 5 times and then stops for 10 seconds, and rotates a total of 50 times in 1 minute.

[0085] (2) A mixed solution of 0.1 g / L sodium hydroxide and 0.2 g / L caustic soda was pumped into the dyeing machine and run for 10 min; the concentrations of caustic soda and sodium hydroxide were calculated based on the total volume of the mixed solution.

[0086] (3) Prepare 12 liters of plant indigo dye solution, weigh the materials in sequence according to the mass concentration ratio of plant indigo, sodium hydroxide and liquid alkali (sodium hydroxide mass concentration is 50%, the balance is water) of 1:10:25, add the liquid alkali, plant indigo and sodium hydroxide into cold water in sequence (the amount of water used for the dissolution of plant indigo and sodium hydroxide is 12 L, and this 12 L of water includes the water in the liquid alkali, and the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25 g / L) and mix them evenly, add a defoaming agent to the obtained dye solution after dissolution, stir and mix evenly to obtain the plant indigo dye solution, and the indigo concentration after dilution is 5 g / L;

[0087] Weighing sodium sulfate and dissolving it in cold water and then mixing it evenly with the plant indigo leuco solution to obtain a mixed solution of plant indigo leuco and sodium sulfate, adding the mixed solution into a dyeing machine to dye the garment, the feeding time is 3 minutes, the bath ratio of the dyeing process is controlled at 1:20, the dyeing temperature is 30°C, and the dyeing time is 10 minutes;

[0088] Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of alum is 10 g / L, and the mass concentration of the defoaming agent is 5 g / L. The defoaming agent is model 3310 produced by Henan Bozhiyuan Water Purification Materials Co., Ltd., and its main component is polyether substances.

[0089] (4) A mixed solution of 3 g / L sodium hypochlorite and 5 g / L liquid alkali was pumped into the dyeing machine and dyeing was continued for 10 minutes. The concentrations of liquid alkali and sodium hypochlorite were calculated based on the total volume of the mixed solution, and the bath ratio of the dyeing process was controlled at 1:20.

[0090] (5) The dyed garments are sequentially subjected to oxidation washing, dehydration, drying, ozone treatment and water softening treatment;

[0091] The bath ratio of the oxidation water washing process is 1:50, the amount of hydrogen peroxide used is 5 g / L based on the total volume of the liquid during the oxidation water washing, and the number of oxidation water washings is 2 times;

[0092] The dehydration speed is 500r / min;

[0093] The drying temperature is 90℃;

[0094] Based on the total volume of the ozone machine used for ozone treatment, the ozone concentration is 1v%, and the treatment time is 5min;

[0095] Based on the total volume of the liquid during the water softening treatment, the amount of softener used in the water softening treatment process is 0.5 g / L, the bath ratio is 1:10, and the water softening treatment time is 5 minutes. The softener is HS-1510 anti-yellow softening oil produced by Zhongshan Hongsheng Biotechnology Co., Ltd.

[0096] After washing and softening, the indigo-dyed garment is obtained.

[0097] Example 3

[0098] This embodiment provides a plant indigo exhaust dyeing process for garments, wherein the process comprises the following specific steps:

[0099] (1) Weigh 3 kg of woven linen shirts and soak them in water at a bath ratio of 1:10 in a garment dyeing machine. The speed of the dyeing machine is set to 5-10-50, that is, the dyeing machine rotates 5 times and then stops for 10 seconds, then reverses 5 times and then stops for 10 seconds, and rotates a total of 50 times in 1 minute.

[0100] (2) A mixed solution of 0.1 g / L sodium hydroxide and 0.2 g / L caustic soda was pumped into the dyeing machine and run for 10 min; the concentrations of caustic soda and sodium hydroxide were calculated based on the total volume of the mixed solution.

[0101] (3) Prepare 6 liters of plant indigo dye solution, weigh each substance in sequence according to the mass concentration ratio of plant indigo, sodium hydroxide and liquid alkali (sodium hydroxide mass concentration is 50%, the balance is water) of 1:10:25, add liquid alkali, plant indigo and sodium hydroxide into cold water (the amount of water used for the dissolution of plant indigo and sodium hydroxide is 6 L, and this 6 L of water includes the water in the liquid alkali, and the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 50 g / L) and mix them evenly, add defoaming agent to the obtained dye solution after dissolution, stir and mix evenly to obtain plant indigo dye solution, and the indigo concentration after dilution is 5 g / L;

[0102] Weighing sodium sulfate and dissolving it in cold water and then mixing it evenly with the plant indigo dye solution to obtain a mixed solution of plant indigo leuco body and sodium sulfate, adding the mixed solution into a dyeing machine to dye the garment, the feeding time is 3 minutes, the bath ratio of the dyeing process is controlled at 1:20, the dyeing temperature is 30°C, and the dyeing time is 10 minutes;

[0103] Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of alum is 10 g / L, and the mass concentration of the defoaming agent is 5 g / L. The defoaming agent is model 3310 produced by Henan Bozhiyuan Water Purification Materials Co., Ltd., and its main component is polyether substances.

[0104] (4) A mixed solution of 3 g / L sodium hypochlorite and 5 g / L liquid alkali was pumped into the dyeing machine and dyeing was continued for 10 minutes. The concentrations of liquid alkali and sodium hypochlorite were calculated based on the total volume of the mixed solution, and the bath ratio of the dyeing process was controlled at 1:20.

[0105] (5) The dyed garments are sequentially subjected to oxidation washing, dehydration, drying, ozone treatment and water softening treatment;

[0106] The bath ratio of the oxidation water washing process is 1:50, the amount of hydrogen peroxide used is 5 g / L based on the total volume of the liquid during the oxidation water washing, and the number of oxidation water washings is 2 times;

[0107] The dehydration speed is 500r / min;

[0108] The drying temperature is 90℃;

[0109] Based on the total volume of the ozone machine used for ozone treatment, the ozone concentration is 1v%, and the treatment time is 5min;

[0110] Based on the total volume of the liquid during the water softening treatment, the amount of softener used in the water softening treatment process is 0.5 g / L, the bath ratio is 1:10, and the water softening treatment time is 5 minutes. The softener is HS-1510 anti-yellow softening oil produced by Zhongshan Hongsheng Biotechnology Co., Ltd.

[0111] After washing and softening, the indigo-dyed garment is obtained.

[0112] Example 4

[0113] This embodiment provides a plant indigo exhaust dyeing process for garments, which differs from the embodiment 1 only in that:

[0114] According to the mass concentration ratio of plant indigo, hydrosulfite and liquid caustic soda of 1:4:2, each substance is weighed in turn, and each substance is added to cold water (the amount of water used when the plant indigo and hydrosulfite are dissolved is 0.24L, and this 0.24L water includes the water in the liquid caustic soda. Accordingly, the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25g / L) and mixed evenly. After dissolving, a defoaming agent is added to the obtained dye solution, and the plant indigo dye solution is obtained after stirring and mixing evenly. The indigo concentration after dilution is 0.1g / L. The local appearance effect of the indigo dyed garment obtained in this embodiment is as follows Figure 6 shown.

[0115] Example 5

[0116] This embodiment provides a plant indigo exhaust dyeing process for garments, which differs from the embodiment 1 only in that:

[0117] For coloring linen fabric, the mass concentration ratio of plant indigo, hydrosulfite and liquid alkali is 1:4:2. Each substance is weighed in turn, and each substance is added to cold water (the amount of water used for the chemical reaction of plant indigo and hydrosulfite is 0.24L, and this 0.24L water includes the water in the liquid alkali. Accordingly, the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25g / L) and mixed evenly. After dissolving, a defoaming agent is added to the obtained dye solution, and the plant indigo dye solution is obtained after stirring and mixing evenly. The indigo concentration after dilution is 0.1g / L. The local appearance effect of the indigo-dyed garment obtained in this embodiment is as follows: Figure 7 shown.

[0118] Example 6

[0119] This embodiment provides a plant indigo exhaust dyeing process for garments, which differs from the embodiment 1 only in that:

[0120] According to the mass concentration ratio of plant indigo, hydrosulfite and liquid caustic soda of 1:4:2, each substance is weighed in turn, and each substance is added to cold water (the amount of water used when the plant indigo and hydrosulfite are dissolved is 4.8L, and this 4.8L of water includes the water in the liquid caustic soda. Accordingly, the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25g / L) and mixed evenly. After dissolving, a defoaming agent is added to the obtained dye solution, and the plant indigo dye solution is obtained after stirring and mixing evenly. The indigo concentration after dilution is 2g / L. The local appearance effect of the indigo dyed garment obtained in this embodiment is as follows Figure 8 shown.

[0121] Example 7

[0122] This embodiment provides a plant indigo exhaust dyeing process for garments, which differs from the embodiment 1 only in that:

[0123] According to the mass concentration ratio of plant indigo, hydrosulfite and liquid caustic soda of 1:4:2, each substance is weighed in turn, and each substance is added to cold water (the amount of water used for the plant indigo and hydrosulfite is 2.4L, and this 2.4L water includes the water in the liquid caustic soda. Accordingly, the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25g / L) and mixed evenly. After dissolving, a defoaming agent is added to the obtained dye solution, and the plant indigo dye solution is obtained after stirring and mixing evenly. The indigo concentration after dilution is 1g / L. The local appearance effect of the indigo dyed garment obtained in this embodiment is as follows Figure 9 shown.

[0124] Example 8

[0125] This embodiment provides a plant indigo exhaust dyeing process for garments, which differs from the embodiment 1 only in that:

[0126] According to the mass concentration ratio of plant indigo, hydrosulfite and liquid caustic soda of 1:16:10, each substance is weighed in sequence, and each substance is added to cold water (the amount of water used when the plant indigo and hydrosulfite are dissolved is 1.2L, and this 1.2L water includes the water in the liquid caustic soda. Accordingly, the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25g / L) and mixed evenly. After dissolving, a defoaming agent is added to the obtained dye solution, and the plant indigo dye solution is obtained after stirring and mixing evenly. The indigo concentration after dilution is 0.5g / L. The local appearance effect of the indigo dyed garment obtained in this embodiment is as follows Figure 10 shown.

[0127] Example 9

[0128] This embodiment provides a plant indigo exhaust dyeing process for garments, which differs from the embodiment 1 only in that:

[0129] According to the mass concentration ratio of plant indigo, hydrosulfite and liquid caustic soda of 1:20:30, each substance is weighed in turn, and each substance is added to cold water (the amount of water used when the plant indigo and hydrosulfite are dissolved is 0.24L, and this 0.24L water includes the water in the liquid caustic soda. Accordingly, the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25g / L) and mixed evenly. After dissolving, a defoaming agent is added to the obtained dye solution, and the plant indigo dye solution is obtained after stirring and mixing evenly. The indigo concentration after dilution is 0.1g / L. The local appearance effect of the indigo dyed garment obtained in this embodiment is as follows Figure 11 shown.

[0130] Among them, in Example 1 and Example 4-Example 9, the mass concentration of plant indigo, the mass concentration of hydrosulfite, the mass concentration of liquid caustic soda and the potential data of plant indigo reducing solution are respectively shown in Table 1 below.

[0131] Table 1

[0132]

[0133] Combined with Table 1 and Figure 1 、 Figure 6-Figure 7 It can be seen that compared to Example 1, Examples 4 and 5 simply reduced the indigo concentration to 0.1 g / L without adjusting the mass concentration ratio of plant indigo, hydrosulfite, and liquid caustic soda, and directly dyed the garments. Although a light-colored dyeing effect was achieved, the dyeing was uneven. For Examples 6 and 7, although the mass concentration ratio of plant indigo, hydrosulfite, and liquid caustic soda was not adjusted, the indigo concentrations used in these two examples were 2 g / L and 1 g / L, respectively, and the resulting dyed garments had bright and uniform colors. For Examples 8 and 9, although the indigo concentrations used were lower, adjusting the mass concentration ratio of plant indigo, hydrosulfite, and liquid caustic soda also achieved the effect of bright and uniform dyeing of the garments.

[0134] In summary, the present invention can achieve uniform coloring of plant indigo from light to medium-dark shades by adjusting formula parameters, such as the concentration ratio of hydrosulfite, caustic soda, and indigo dye in the indigo dye solution. That is, by regulating the redox potential and pH of the dye solution through a reduction method, a uniform dyeing effect from ultra-light to medium-dark shades can be achieved.

[0135] Comparative Example 1

[0136] This comparative example provides a garment plant indigo exhaust dyeing process, wherein the process comprises the following specific steps:

[0137] (1) Weigh 3 kg of knitted pure cotton round-neck T-shirts and place them in a garment dyeing machine, add water at a bath ratio of 1:10 and soak them. The speed of the dyeing machine is set to 5-10-50, that is, the dyeing machine rotates 5 times and then stops for 10 seconds, then reverses 5 times and then stops for 10 seconds, and rotates a total of 50 times in 1 minute.

[0138] (2) preparing 12 liters of plant indigo dye solution, weighing each substance in sequence according to the mass concentration ratio of plant indigo, sodium hydroxide and liquid alkali (sodium hydroxide mass concentration is 50%, the balance is water) of 1:4:2, adding the liquid alkali, plant indigo and sodium hydroxide into cold water (the amount of water used for the dissolution of plant indigo and sodium hydroxide is 12 L, and this 12 L of water includes the water in the liquid alkali, and the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25 g / L) and mixing them evenly, adding a defoaming agent to the obtained dye solution after dissolution, stirring and mixing evenly to obtain a plant indigo dye solution, and the indigo concentration after dilution is 5 g / L;

[0139] Weighing sodium sulfate and dissolving it in cold water and then mixing it evenly with the plant indigo dye solution to obtain a mixed solution of plant indigo leuco body and sodium sulfate, adding the mixed solution into a dyeing machine to dye the garment, the feeding time is 3 minutes, the bath ratio of the dyeing process is controlled at 1:20, the dyeing temperature is 30°C, and the dyeing time is 10 minutes;

[0140] Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of alum is 10 g / L, and the mass concentration of the defoaming agent is 5 g / L. The defoaming agent is model 3310 produced by Henan Bozhiyuan Water Purification Materials Co., Ltd., and its main component is polyether substances.

[0141] (3) A mixed solution of 3 g / L sodium hypochlorite and 5 g / L liquid alkali was pumped into the dyeing machine and dyeing was continued for 10 min. The concentrations of liquid alkali and sodium hypochlorite were calculated based on the total volume of the mixed solution, and the bath ratio of the dyeing process was controlled at 1:20.

[0142] (4) The dyed garments are sequentially subjected to oxidation washing, dehydration, drying, ozone treatment and water softening treatment;

[0143] The bath ratio of the oxidation water washing process is 1:50, the amount of hydrogen peroxide used is 5 g / L based on the total volume of the liquid during the oxidation water washing, and the number of oxidation water washings is 2 times;

[0144] The dehydration speed is 500r / min;

[0145] The drying temperature is 90℃;

[0146] Based on the total volume of the ozone machine used for ozone treatment, the ozone concentration is 1v%, and the treatment time is 5min;

[0147] Based on the total volume of the liquid during the water softening treatment, the amount of softener used in the water softening treatment process is 0.5 g / L, the bath ratio is 1:10, and the water softening treatment time is 5 minutes. The softener is HS-1510 anti-yellow softening oil produced by Zhongshan Hongsheng Biotechnology Co., Ltd.

[0148] After washing and softening, the indigo-dyed garment is obtained, and its local appearance effect is as follows Figure 2 shown.

[0149] Comparative Example 2

[0150] This comparative example provides a garment plant indigo exhaust dyeing process, wherein the process comprises the following specific steps:

[0151] (1) Weigh 3 kg of knitted pure cotton round-neck T-shirts and place them in a garment dyeing machine, add water at a bath ratio of 1:10 and soak them. The speed of the dyeing machine is set to 5-10-50, that is, the dyeing machine rotates 5 times and then stops for 10 seconds, then reverses 5 times and then stops for 10 seconds, and rotates a total of 50 times in 1 minute.

[0152] (2) A mixed solution of 0.1 g / L sodium hydroxide and 0.2 g / L caustic soda was pumped into the dyeing machine and run for 10 min; the concentrations of caustic soda and sodium hydroxide were calculated based on the total volume of the mixed solution.

[0153] (3) Prepare 12 liters of plant indigo dye solution, weigh each substance in sequence according to the mass concentration ratio of plant indigo, sodium hydroxide and liquid alkali (sodium hydroxide mass concentration is 50%, the balance is water) of 1:4:2, add liquid alkali, plant indigo and sodium hydroxide into cold water in sequence (the amount of water used for the dissolution of plant indigo and sodium hydroxide is 12 L, and this 12 L of water includes the water in the liquid alkali, and the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25 g / L) and mix them evenly, add defoaming agent to the obtained dye solution after dissolution, stir and mix evenly to obtain plant indigo dye solution, and the indigo concentration after dilution is 5 g / L;

[0154] The plant indigo dye solution was added into the dyeing machine to dye the garment. The addition time was 3 minutes, the bath ratio of the dyeing process was controlled at 1:20, the dyeing temperature was 30°C, and the dyeing time was 10 minutes.

[0155] Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of the defoaming agent is 5 g / L. The defoaming agent is model 3310 produced by Henan Bozhiyuan Water Purification Materials Co., Ltd., and its main component is polyether substances.

[0156] (4) A mixed solution of 3 g / L sodium hypochlorite and 5 g / L liquid caustic soda was pumped into the dyeing machine and dyeing was continued for 10 minutes, wherein the concentrations of liquid caustic soda and sodium hypochlorite were calculated based on the total volume of the mixed solution.

[0157] (5) The dyed garments are sequentially subjected to oxidation washing, dehydration, drying, ozone treatment and water softening treatment;

[0158] The bath ratio of the oxidation water washing process is 1:50, the amount of hydrogen peroxide used is 5 g / L based on the total volume of the liquid during the oxidation water washing, and the number of oxidation water washings is 2 times;

[0159] The dehydration speed is 500r / min;

[0160] The drying temperature is 90℃;

[0161] Based on the total volume of the ozone machine used for ozone treatment, the ozone concentration is 1v%, and the treatment time is 5min;

[0162] Based on the total volume of the liquid during the water softening treatment, the amount of softener used in the water softening treatment process is 0.5 g / L, the bath ratio is 1:10, and the water softening treatment time is 5 minutes. The softener is HS-1510 anti-yellow softening oil produced by Zhongshan Hongsheng Biotechnology Co., Ltd.

[0163] After washing and softening, the indigo-dyed garment is obtained, and its local appearance effect is as follows Figure 3 shown.

[0164] Comparative Example 3

[0165] This comparative example provides a garment plant indigo exhaust dyeing process, wherein the process comprises the following specific steps:

[0166] (1) Weigh 3 kg of knitted pure cotton round-neck T-shirts and place them in a garment dyeing machine, add water at a bath ratio of 1:10 and soak them. The speed of the dyeing machine is set to 5-10-50, that is, the dyeing machine rotates 5 times and then stops for 10 seconds, then reverses 5 times and then stops for 10 seconds, and rotates a total of 50 times in 1 minute.

[0167] (2) A mixed solution of 0.1 g / L sodium hydroxide and 0.2 g / L caustic soda was pumped into the dyeing machine and run for 10 min; the concentrations of caustic soda and sodium hydroxide were calculated based on the total volume of the mixed solution.

[0168] (3) Prepare 12 liters of plant indigo dye solution, weigh each substance in sequence according to the mass concentration ratio of plant indigo, sodium hydroxide and liquid alkali (sodium hydroxide mass concentration is 50%, the balance is water) of 1:4:2, add liquid alkali, plant indigo and sodium hydroxide into cold water in sequence (the amount of water used for the dissolution of plant indigo and sodium hydroxide is 12 L, and this 12 L of water includes the water in the liquid alkali, and the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25 g / L) and mix them evenly, add defoaming agent to the obtained dye solution after dissolution, stir and mix evenly to obtain plant indigo dye solution, and the indigo concentration after dilution is 5 g / L;

[0169] Weighing sodium sulfate and dissolving it in cold water and then mixing it evenly with the plant indigo dye solution to obtain a mixed solution of plant indigo leuco body and sodium sulfate, adding the mixed solution into a dyeing machine to dye the garment, the feeding time is 3 minutes, the bath ratio of the dyeing process is controlled at 1:20, the dyeing temperature is 30°C, and the dyeing time is 10 minutes;

[0170] Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of alum is 10 g / L, and the mass concentration of the defoaming agent is 5 g / L. The defoaming agent is model 3310 produced by Henan Bozhiyuan Water Purification Materials Co., Ltd., and its main component is polyether substances.

[0171] (4) The dyed garments are sequentially subjected to oxidation washing, dehydration, drying, ozone treatment and water softening treatment;

[0172] The bath ratio of the oxidation water washing process is 1:50, the amount of hydrogen peroxide used is 5 g / L based on the total volume of the liquid during the oxidation water washing, and the number of oxidation water washings is 2 times;

[0173] The dehydration speed is 500r / min;

[0174] The drying temperature is 90℃;

[0175] Based on the total volume of the ozone machine used for ozone treatment, the ozone concentration is 1v%, and the treatment time is 5min;

[0176] Based on the total volume of the liquid during the water softening treatment, the amount of softener used in the water softening treatment process is 0.5 g / L, the bath ratio is 1:10, and the water softening treatment time is 5 minutes. The softener is HS-1510 anti-yellow softening oil produced by Zhongshan Hongsheng Biotechnology Co., Ltd.

[0177] After washing and softening, the indigo-dyed garment is obtained, and its local appearance effect is as follows Figure 4 shown.

[0178] Comparative Example 4

[0179] This comparative example provides a garment plant indigo exhaust dyeing process, wherein the process comprises the following specific steps:

[0180] (1) Weigh 3 kg of knitted pure cotton round-neck T-shirts and place them in a garment dyeing machine, add water at a bath ratio of 1:10 and soak them. The speed of the dyeing machine is set to 5-10-50, that is, the dyeing machine rotates 5 times and then stops for 10 seconds, then reverses 5 times and then stops for 10 seconds, and rotates a total of 50 times in 1 minute.

[0181] (2) A mixed solution of 0.1 g / L sodium hydroxide and 0.2 g / L caustic soda was pumped into the dyeing machine and run for 10 min; the concentrations of caustic soda and sodium hydroxide were calculated based on the total volume of the mixed solution.

[0182] (3) Prepare 12 liters of plant indigo dye solution, weigh each substance in sequence according to the mass concentration ratio of plant indigo, sodium hydroxide and liquid alkali (sodium hydroxide mass concentration is 50%, the balance is water) of 1:4:2, add liquid alkali, plant indigo and sodium hydroxide into cold water (the amount of water used to dissolve plant indigo and sodium hydroxide is 12 L, and this 12 L of water includes the water in the liquid alkali. Accordingly, the concentration of plant indigo when preparing the plant indigo dye solution outside the dyeing machine is 25 g / L) and mix them evenly. After dissolving, add defoaming agent to the obtained dye solution, stir and mix evenly to obtain plant indigo dye solution. The indigo concentration after dilution is 5 g / L, and the plant indigo dye solution is pumped into the dyeing machine.

[0183] (4) Weighing sodium sulfide and dissolving it with cold water and then pumping it into the dyeing machine, the total feeding time of step (3) and step (4) is 3 minutes, the bath ratio of the dyeing process is controlled at 1:20, the dyeing temperature is 30° C., and the dyeing time is 10 minutes;

[0184] Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of alum is 10 g / L, and the mass concentration of the defoaming agent is 5 g / L. The defoaming agent is model 3310 produced by Henan Bozhiyuan Water Purification Materials Co., Ltd., and its main component is polyether substances.

[0185] (5) A mixed solution of 3 g / L sodium hydroxide and 5 g / L liquid alkali was pumped into the dyeing machine and dyeing was continued for 10 minutes. The concentrations of liquid alkali and sodium hydroxide were calculated based on the total volume of the mixed solution, and the bath ratio of the dyeing process was controlled at 1:20.

[0186] (6) The dyed garments are sequentially subjected to oxidation washing, dehydration, drying, ozone treatment and water softening treatment;

[0187] The bath ratio of the oxidation water washing process is 1:50, the amount of hydrogen peroxide used is 5 g / L based on the total volume of the liquid during the oxidation water washing, and the number of oxidation water washings is 2 times;

[0188] The dehydration speed is 500r / min;

[0189] The drying temperature is 90℃;

[0190] Based on the total volume of the ozone machine used for ozone treatment, the ozone concentration is 1v%, and the treatment time is 5min;

[0191] Based on the total volume of the liquid during the water softening treatment, the amount of softener used in the water softening treatment process is 0.5 g / L, the bath ratio is 1:10, and the water softening treatment time is 5 minutes. The softener is HS-1510 anti-yellow softening oil produced by Zhongshan Hongsheng Biotechnology Co., Ltd.

[0192] After washing and softening, the indigo-dyed garment is obtained, and its local appearance effect is as follows Figure 5 shown.

[0193] Test Example 1

[0194] In this test example, the full set of color fastness (i.e., including soaping, dry and wet friction, perspiration, washing, sun exposure, perspiration and sun exposure color fastness), sun fastness and light perspiration composite color fastness of the indigo-dyed garments prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were tested in accordance with relevant national standards. The test results are shown in Table 2 below.

[0195] Table 2 Color fastness data of indigo dyed garments prepared in Examples and Comparative Examples

[0196]

[0197] This test example also uses a DataColor 400 colorimeter to test the color saturation (C value) and other color characteristics of the indigo-dyed garments produced in Example 1 and Comparative Examples 1-4. During the test, a D6s light source and a 10° observation angle were used. Each sample was folded into two layers and measured at different locations for n>3 times. The average value was taken until the error was <0.3. The larger the C value of the garment, the higher its saturation, the purer the dyed color, and the more vivid the color.

[0198] The test results obtained in this test example are shown in Table 3 below.

[0199] Table 3 Color brightness data of indigo dyed garments prepared in Examples and Comparative Examples

[0200] L a b K / S C Example 1 30.78 -0.78 -23.64 8.6933 23.65 Comparative Example 1 43.72 -3.54 -22.39 7.4373 22.67 Comparative Example 2 52.48 -4.22 -11.62 3.1706 12.36 Comparative Example 3 40.66 -3.47 -19.22 7.5299 19.53 Comparative Example 4 46.94 -4.24 -15.81 3.6521 16.37

[0201] From the experimental data in Table 2 above, it can be seen that the color fastness of the indigo-dyed garments prepared in Examples 1 to 3 of the present invention meets the first-class standard for plant dyes and meets the requirements for wearing. In addition, the washing fastness and wet rubbing fastness are 0.5-2.5 grades higher than those of the indigo-dyed garments prepared in Comparative Examples 1 to 3.

[0202] From the experimental data in Table 3 above, it can be seen that the color saturation C value of the indigo-dyed garment obtained in Example 1 of the present invention is the highest, the most vivid, the KS value is also higher, and the b value is the largest, indicating that the blue light is the most positive. The color saturation C value of the indigo-dyed garment obtained in Comparative Example 2 is much lower than that in Example 1, and the actual vividness is also relatively much worse, and the overall color is grayish. This shows that no sodium sulfate solution is added during the dyeing process, and the overall dyeing vividness of plant indigo dyeing is obviously not as good as the plant indigo dyeing effect when the plant indigo dye solution and sodium sulfate solution are mixed and added to the dyeing machine to dye the garment. However, the L value of the indigo-dyed garment obtained in Comparative Example 2 is larger, indicating that the color yield is low, the brightness will be relatively larger, but the color saturation is low;

[0203] Secondly, the KS value and color saturation C value of the indigo-dyed garments prepared in Comparative Examples 2 and 3 are lower than those in Example 1, and the b value is relatively small, indicating that the blue light is not positive enough and the color saturation is not good enough.

[0204] In addition, the color saturation C value of the indigo-dyed garment obtained in Comparative Example 4 is significantly lower than that in Example 1, and the KS value is also significantly smaller, indicating that the apparent color yield is low and the dye is not fully dyed. In Comparative Example 4, the addition of a high concentration of sodium sulfate during the dyeing process will cause the local dyeing rate to be too high when the fabric is dyed, and the dyeing will continue to be oxidized by the air. The dye liquor itself has unevenness, and only part of the sodium sulfate can promote the dyeing of the plant indigo dye on the fabric. When the sodium sulfate solution enters the dyeing machine, the plant indigo dye liquor has been partially oxidized and cannot play a good role in purifying the dye liquor. Therefore, the plant indigo dyeing process for garments provided by the embodiment of the present invention mixes the sodium sulfate solution with the plant indigo dye liquor in advance, and then pumps it into the dyeing machine after the effect is sufficient. It can achieve the purpose of secondary purification of plant indigo dye, improve color saturation and vividness, and promote the dyeing of fabric before the indigo dye is oxidized. After the secondary purification, the impurities on the fabric surface are reduced, thereby also improving the friction fastness of plant indigo to a certain extent.

[0205] Furthermore, compared to Example 1, Comparative Example 1 did not add a mixed solution of liquid caustic soda and hydrosulfite to the dyeing machine before dyeing. As shown in the experimental data in Table 3, the K / S and C values ​​of the indigo-dyed garment produced in Comparative Example 1 decreased, indicating that its apparent color depth decreased while its color saturation also decreased. Furthermore, the absolute value of the negative b value of the indigo-dyed garment produced in Comparative Example 1 also decreased, indicating a weakening of its blue light, while the absolute value of the negative a value increased, indicating a greenish tint. The L value increased as the color became lighter. In short, the overall color vividness of the indigo-dyed garment produced in Comparative Example 1 was insufficient.

[0206] For example Figure 1-Figure 5As shown in the local appearance effects of the indigo-dyed garments prepared in Example 1 and Comparative Examples 1 to 4, the indigo-dyed garment prepared in Example 1 of the present invention has a uniform color, a medium-dark color depth, a pure color, and a soft color.

[0207] The indigo-dyed garment obtained in Comparative Example 1 had a relatively light surface color and small white spots. This indicates that insufficient dye diffusion occurred during dyeing, causing the dye to float on the fabric surface. Most of the ozone bleaching was removed, resulting in a hazy surface color and an overall unrefined dyeing. By comparison, adding a mixed solution of caustic soda and hydrosulfite to the dyeing machine before dyeing can, to a certain extent, over-reduce the indigo dye liquor during dyeing, converting the indigo leucophenolate from sodium monophenolate to sodium bisphenolate, increasing the solubility of the indigo leucophenolate and thereby increasing the activation energy for the diffusion of the dye from the solution into the fiber.

[0208] The indigo dyed garment obtained in Comparative Example 2 has a grayish color, a dull color, and is not blue enough. The white marks on the shirt body are obvious, and it is difficult to dye evenly. The indigo dyed garment obtained in Comparative Example 3 has a more flowery color, is not dyed solidly, and the surface of the fabric is whitish. There are obvious white flower marks, which are difficult to dye evenly, and the color is dull. Similarly, the indigo dyed garment obtained in Comparative Example 4 has a more flowery color, is not dyed solidly, has dark flower spots and white stripes on the surface of the fabric, and is grayish in color. This shows that in Comparative Examples 1 to 4, no mixed solution of liquid alkali and insurance powder was added to the dyeing machine before dyeing, no sodium sulfate solution was used during dyeing, no mixed solution of liquid alkali and insurance powder was added to the dyeing machine after dyeing for a period of time, and sodium sulfate solution was added to the dyeing machine after dyeing started. None of the above can achieve the purpose of making the indigo dyed garment unique in style, uniform in color, bright in color, fresh and natural in style, high in color fastness, and in compliance with the first-class standard of plant dyes, and meeting subsequent wearing requirements.

[0209] In summary, the plant indigo dyeing process for garments provided by the embodiments of the present invention has the advantages of simple process, short dyeing time, convenient operation, re-dyeing and repair, and good stability; the indigo-dyed garments obtained by the process have a unique style, uniform color, bright color, fresh and natural style, high color fastness and meet the first-class plant dye standards, meeting subsequent wearing requirements.

[0210] The above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, substitutions of equivalent components, or equivalent changes and modifications made within the scope of patent protection, should still fall within the scope of this patent. Furthermore, the technical features of this invention may be freely combined with one another, with other technical inventions, and with other technical inventions.

Claims

1. A garment plant indigo dyeing process, characterized in that: The garment plant indigo exhaust dyeing process comprises: (1) Place the garment to be dyed into a non-air-insulated dyeing machine and add water for soaking; (2) Pumping the mixed solution of liquid alkali and hydrosulfite into the dyeing machine and running the dyeing machine to eliminate part of the oxygen in the dyeing machine; (3) weighing each substance in sequence according to the mass concentration of plant indigo being 5-80 g / L and the mass concentration ratio of plant indigo, hydrosulfite and liquid caustic soda being 1:1-40:1-50, adding each substance into cold water and mixing them evenly, adding a defoaming agent into the obtained dye solution, and mixing them evenly to obtain a plant indigo dye solution, wherein the potential value of the plant indigo dye solution ranges from -760 mV to -1000 mV; mixing the plant indigo dye solution and a sodium sulfate solution, and adding the mixture into a dyeing machine to dye the garment, wherein the mass concentration of the sodium sulfate is 5-80 g / L, and the mass concentration of the defoaming agent is 0.1-5 g / L, based on the total volume of the liquid in the dyeing machine; (4) Pumping the mixed solution of liquid alkali and hydrosulfite into the dyeing machine to continue dyeing the garment; (5) The dyed garments are subjected to oxidation washing, dehydration, drying, ozone treatment and water softening treatment to obtain indigo dyed garments.

2. The plant indigo exhaust dyeing process for garments according to claim 1, characterized in that: The fabric of the garment includes natural fiber fabric, chemical fiber fabric or blended fabric of natural fiber and chemical fiber.

3. The plant indigo exhaust dyeing process for garments according to claim 2, characterized in that: The natural fibers include one or more of cotton, linen, silk and wool.

4. The plant indigo exhaust dyeing process for garments according to claim 2, characterized in that: The chemical fibers include one or more of acrylic, viscose, nylon and polyester.

5. The plant indigo exhaust dyeing process for garments according to any one of claims 1 to 4, characterized in that: The dyeing machine rotates 5-20 times and then stops for 1-10 seconds, then reverses for 5-20 times and then stops for 1-10 seconds, and rotates a total of 10-50 times within 1 minute. The running time of the dyeing machine is 3-30 minutes.

6. The process for plant indigo exhaust dyeing of garments according to claim 5, characterized in that: In step (1), the bath ratio of the garment to water is 1:10-50.

7. The process for plant indigo exhaust dyeing of garments according to claim 1, characterized in that: In step (2), in the mixed solution of liquid caustic soda and sodium hypochlorite, based on the total volume of the mixed solution, the concentration of liquid caustic soda is 0.2-10 g / L, and the concentration of sodium hypochlorite is 0.1-10 g / L.

8. The plant indigo exhaust dyeing process for garments according to claim 1 or 7, characterized in that: In step (2), the dyeing operation time of the dyeing machine is 3-30 minutes.

9. The process for plant indigo exhaust dyeing of garments according to claim 1, wherein: In step (4), in the mixed solution of liquid caustic soda and sodium hypochlorite, based on the total volume of the mixed solution, the concentration of liquid caustic soda is 0.1-2 g / L, and the concentration of sodium hypochlorite is 0.5-5 g / L.

10. The plant indigo exhaust dyeing process for garments according to claim 1 or 9, characterized in that: In step (4), the dyeing time is 1-20 minutes.

11. The process for plant indigo exhaust dyeing of garments according to claim 1, characterized in that: Weigh each substance in sequence according to the mass concentration of plant indigo of 10-50 g / L and the mass concentration ratio of plant indigo, hydrosulfite and liquid caustic soda of 1:1-30:1-40, add each substance into cold water and mix well, then add a defoaming agent to the obtained dye solution, and mix well to obtain a plant indigo dye solution; Calculated based on the total volume of liquid during dyeing in the dyeing machine, the mass concentration of sodium sulfate is 10-60g / L.

12. The plant indigo exhaust dyeing process for garments according to claim 1 or 11, characterized in that: The pH value of the plant indigo dye solution is in the range of 11-13.

13. The plant indigo exhaust dyeing process for garments according to claim 1 or 11, characterized in that: In step (3), the dyeing machine is first operated for 2-30 minutes, and then the plant indigo dye solution and the sodium sulfate solution are mixed and added into the dyeing machine, wherein the feeding time is 2-20 minutes. After all the mixed solution is added into the dyeing machine, the dyeing machine is continued to operate for 2-30 minutes to dye the finished garment, wherein the dyeing temperature is 30-60°C.

14. The process for plant indigo exhaust dyeing of garments according to claim 1, wherein: In step (5), the bath ratio of the oxidation water washing process is 1:10-50, the amount of hydrogen peroxide used is 0.1-10 g / L based on the total volume of the liquid during the oxidation water washing, the oxidation water washing time is 1-30 min, and the number of oxidation water washings is 1-10 times.

15. The process for plant indigo exhaust dyeing of garments according to claim 1 or 14, characterized in that: In step (5), the dehydration speed is 100-500 r / min.

16. The process for plant indigo exhaust dyeing of garments according to claim 1 or 14, characterized in that: In step (5), the drying temperature is 50-90°C.

17. The process for plant indigo exhaust dyeing of garments according to claim 1 or 14, characterized in that: In step (5), the ozone concentration is 1-20v%, based on the total volume of the ozone machine used for ozone treatment, and the treatment time is 5-50min.

18. The process for plant indigo exhaust dyeing of garments according to claim 1 or 14, characterized in that: In step (5), based on the total volume of the liquid during the over-softening treatment of the washing water, the amount of softener used in the over-softening treatment of the washing water is 0.5-5 g / L, the bath ratio is 1:10-50, and the time for the over-softening treatment of the washing water is 5-30 min.

19. The process for plant indigo exhaust dyeing of garments according to claim 18, wherein: The softener is an antioxidant softener.

20. The process according to any one of claims 1 to 4, characterized in that The ready-made clothes are cotton and linen ready-made clothes.

21. An indigo-dyed garment, characterized in that: The indigo-dyed garment is produced by the garment plant indigo exhaust dyeing process according to any one of claims 1 to 20.

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