Preparation of sand-coated clothes and processing method

Abstract

The present application relates to the technical field of textile dyeing and finishing, and particularly relates to a preparation method of a sand-coagulation and dirt-washing style garment and a processing method, which comprises the following steps: pretreatment, preparation of leuco body, dyeing, liquid carrying and uniforming, oxidation and color development, washing and softening, and post-finishing. By controlling key parameters such as liquid carrying rate, uniforming time, rotating speed, temperature and pH value, the present application ensures that the leuco body is roughly uniformly distributed in the garment fibers, and the sand-coagulation and dirt-washing style garment effect is obtained after oxidation. By the combination process of dyeing with leuco body of reducible dyes and in-situ oxidation and color development, the present application realizes the dirt-washing style effect of the garment, and innovatively introduces the liquid carrying and uniforming process, thereby solving the color mottle problem which is prone to occur in the garment dyeing with reducible dyes. The present application can obtain the dirt-washing effect with higher color fastness, and the original hand feeling and functionality of the fabric are not affected, and can be widely applied to the dirt-washing style processing of garments made of natural fibers such as cotton, hemp, silk and wool, and regenerated cellulose fibers such as viscose and lyocell.

Description

Technical Field

[0001] This invention relates to the field of textile dyeing and finishing technology, and in particular to a method for preparing and processing garments with a sand-dyed, dirty-wash style. Background Technology

[0002] The distressed look is a popular garment finishing technique in recent years. It simulates the natural wear, fading, and discoloration of clothing after long-term wear, giving garments a vintage, aged appearance. Traditional distressed washing primarily uses pigment dyeing to achieve this effect. However, this method often suffers from problems such as a stiff feel, poor rubbing resistance, and compromised fabric functionality.

[0003] Reducible dyes possess excellent properties such as natural color, a complete color spectrum, and good light and wash fastness, making them widely used in textile dyeing. The uniformity of dyeing is primarily improved by controlling parameters such as dyeing temperature, time, and pH value. However, because dyeing with reducible dyes requires multiple steps including reduction, dyeing, and oxidation, rapid dye oxidation during garment dyeing easily leads to problems such as uneven coloring. Therefore, few manufacturers use reducible dyes for garment dyeing. Thus, developing a garment processing method using reducible dyes that can achieve a distressed wash effect while overcoming poor color fastness is of significant practical importance. Summary of the Invention

[0004] To address the problems of complex processes, high costs, significant fiber damage, and severe environmental pollution associated with existing dirty washing processes, and to solve the issues of poor color fastness and color unevenness that easily occur during garment dyeing, this invention provides a method for preparing and processing garments with a sand-dyed dirty wash style. This method features high color fastness, preserves the original feel and functionality of the fabric, and achieves the sand-dyed dirty wash style effect.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A processing method for preparing garments with a sand-dyed and dirty wash style includes the following steps:

[0007] Step 1, Pretreatment: The garment is desized and scouring to remove impurities and improve the hygroscopicity and reactivity of the fibers;

[0008] Step 2, Leuco preparation: The reducible dye is added to an aqueous solution containing a reducing agent and an alkali, and reduced to a soluble leuco sodium salt at a certain temperature;

[0009] Step 3, dyeing: Immerse the pretreated garment in the leuco dye solution for dyeing, or apply the leuco dye solution to the garment by spraying.

[0010] Step 4, Liquid uniformity: After dyeing, control the liquid content of the garment to be between 30% and 150%, and rotate it in a rotating drum at a speed of 8-15 r / min for 3-30 minutes, while maintaining the temperature at 25-60℃ and the pH value between 10-14, so that the leuco pigment is evenly distributed inside the garment fibers.

[0011] Step 5, Oxidation and Color Development: Expose the homogenized garment to air for oxidation, or use an oxidizing agent for oxidation;

[0012] Step 6, Washing and softening: Wash and soften the oxidized garments.

[0013] Step 7, Finishing: After softening, the garment is dehydrated, dried and shaped to obtain a garment with a sand-dyed and dirty wash style.

[0014] By adopting the above technical solution, in the above liquid-carrying and homogenization steps, the leuco pigment remains soluble after dyeing. Controlling the temperature between 25-60℃ and the pH value between 10-14 maintains the stability of the leuco pigment and prevents premature oxidation by air during the homogenization process. The core purpose of controlling the liquid carry-over rate at 30%-150% is to ensure sufficient liquid medium inside the garment, allowing leuco pigment molecules to migrate in the liquid phase between fibers. Simultaneously, slow rotation at a low speed of 8-15 r / min for 3-30 minutes promotes uniform exchange of dye solution throughout the garment, preventing the dye solution from being thrown out or concentrating at the edges due to excessive centrifugal force.

[0015] Further, in step 4, at least one of a leveling agent and a reducing agent supplement is added during the homogenization process; the amount of the leveling agent is 0.5~5g / L, and the amount of the reducing agent supplement is 5%~10% of the weight of the vat dye.

[0016] Furthermore, in step 4, an anti-migration agent is added during the homogenization process, with a dosage of 1-10 g / L.

[0017] Furthermore, in step 5, the oxidation method also includes in-situ oxidation during the drying process: the homogenized garment is dried in a rotary drum at 60-110°C for 5-60 minutes, so that the leuco pigment oxidizes simultaneously during the drying process.

[0018] Furthermore, steps 1 to 7 employ a soaking-dehydration-drying method, specifically as follows:

[0019] Immerse the pretreated garments in leuco dye solution at 25-60℃ for 5-30 minutes;

[0020] Dehydrate the soaked garments until the liquid content is 45%-150%;

[0021] After dehydration, the garment is rotated in a drum at 8-10 r / min for 5-30 minutes to homogenize the liquid.

[0022] After homogenization, the garment is dried in a rotary drum at 60-110℃ for 5-60 minutes to allow the leuco pigment to oxidize during the drying process.

[0023] The dried garments are then washed, softened, and finished.

[0024] Furthermore, steps 1 to 7 employ the spray-homogenization-heating method, specifically as follows:

[0025] The pre-treated garments are placed in a rotating drum and rotated at a speed of 10-15 r / min;

[0026] The leuco dye solution is evenly sprayed onto the garment using a spray method, with the liquid retention rate controlled between 30% and 150%.

[0027] Continue rotating at 10-15 r / min for 5-30 minutes to homogenize the liquid;

[0028] Heat the rotating drum to 60-110℃ and rotate it for 5-60 minutes to allow the leuco form to oxidize during the heating process.

[0029] The oxidized garments are then washed, softened, and finished.

[0030] Furthermore, the reducible dye is selected from one or more of sulfide, indigo, anthraquinone, indigo group, or fused ring vat dyes.

[0031] The present invention also provides a garment with a sand-dyeing and dirty-wash style, which is made by the above-described processing method.

[0032] Furthermore, the garment is made of natural fibers such as cotton, linen, silk, and wool, as well as regenerated cellulose fibers such as viscose, lyocell, modal, bamboo viscose fiber, and cupro fiber.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. This invention effectively solves the problem of color spots that easily occur in garment dyeing with reductive dyes by introducing a liquid homogenization process.

[0035] 2. This invention combines the leuco dyeing of reducible dyes with in-situ oxidation color development, realizing a one-step preparation of garments with a dirty wash style, simplifying the process and reducing costs.

[0036] 3. The method of the present invention uses dyeable dyeing, which avoids the drawbacks of poor friction fastness, stiff hand feel and reduced fabric function caused by the use of paint dyeing in traditional dirty washing process.

[0037] 4. By controlling the type, concentration, homogenization parameters, and oxidation conditions of reducible dyes, this invention can precisely regulate the depth, hue, and degree of distressing of the dirty wash style, meeting the needs of different consumers.

[0038] 5. The method of the present invention can be widely applied to the dirty washing style processing of garments made of natural fibers such as cotton, linen, silk, and wool, as well as regenerated cellulose fiber fabrics such as viscose, lyocell, modal, bamboo viscose fiber, and cupro fiber, and its application range is wide. Detailed Implementation

[0039] The technical solutions in the embodiments of the present invention will be clearly and completely described below, so that those skilled in the art can better understand the advantages and features of the present invention, thereby making a clearer definition of the scope of protection of the present invention. The embodiments described in this invention are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0040] Example 1: Preparation of pure cotton garments with sand-dyed and soiled wash style using the soaking-dehydration-drying method

[0041] Pretreatment: The pure cotton garments are desized and scalded to remove impurities;

[0042] Preparation of leuco form: 10 g / L indigo dye was added to an aqueous solution containing 35 g / L sodium hydrosulfite and 15 g / L sodium hydroxide, and the solution was reduced at 55°C for 20 minutes to obtain the leuco dye solution;

[0043] Dyeing: Immerse the pretreated pure cotton garment in the leuco dye solution and soak at 30°C for 15 minutes;

[0044] Liquid homogenization: After soaking, the garment is dehydrated to a liquid content of 80%, placed in a rotating drum and rotated at 9 r / min for 8 minutes, while maintaining a temperature of 30℃ and a pH of 12.

[0045] Oxidation color development: After homogenization, the garment is dried in a rotary drum at 90°C for 10 minutes to allow the leuco pigment to oxidize and develop color during the drying process;

[0046] Softening by washing: Wash the oxidized garment to remove loose dye, and then soften it with 2g / L of softener.

[0047] Finishing: The softened garments are dehydrated, dried and shaped to obtain pure cotton garments with a sandy, dirty wash style.

[0048] Example 2: Preparation of dirty-wash style hemp garments by spray-homogenization-heating electrophoresis

[0049] Pretreatment: The hemp garments are desized, boiled, and bleached;

[0050] Preparation of leuco form: Add 8 g / L Vat Blue RSN dye to an aqueous solution containing 18 g / L sodium hydrosulfite and 20 g / L sodium hydroxide, and reduce at 60°C for 15 minutes to obtain leuco dye solution;

[0051] Dyeing: Place the pretreated hemp garment into a rotating drum and rotate it at 12 r / min. Spray the leuco dye solution evenly onto the garment using a spray method, controlling the liquid carry-over rate to 90%.

[0052] Liquid homogenization: Continue to rotate at 12 r / min for 20 minutes to homogenize the liquid, maintaining a temperature of 28℃ and a pH of 12.5;

[0053] Oxidation color development: Heat the rotating drum to 95°C and rotate it for 12 minutes to allow the leuco form to oxidize and develop color during the heating process;

[0054] Softening by washing: Wash the oxidized garment to remove loose dye, and then soften it with 3g / L of softener.

[0055] Finishing: The softened garments are dehydrated, dried and shaped to obtain hemp garments with a uniform dirty wash style.

[0056] Experiment 1: The comparison results between the method of the present invention (Example 2) and the comparative example (traditional garment dyeing and stain washing) are shown in Table 1 below:

[0057] Table 1

[0058] Wash fastness Level 4 Level 4-5 GB / T 3921-2008 Textiles - Tests for color fastness - Color fastness to washing Dry rubbing fastness Level 3-4 Level 4 GB / T 3920-2008 Textiles - Tests for color fastness - Color fastness to rubbing fastness to wet rubbing Level 2-3 Level 3-4 GB / T 3920-2008 Textiles - Tests for color fastness - Color fastness to rubbing Light fastness Level 3 Level 4 GB / T 8427-2019 Textiles – Tests for color fastness: Color fastness to artificial light – Xenon arc fastness to perspiration Level 3-4 Level 4 GB / T 3922-2013 "Textiles - Tests for color fastness: Color fastness to perspiration" hygroscopic 7.5s 2.4s GB / T 21655.1-2023 "Evaluation of the moisture absorption and quick-drying properties of textiles – Part 1: Single-item combination test method" - Water droplet diffusion method

[0059] In summary, the method of the present invention has the advantages of simple process, low cost, environmental friendliness, high color fastness, soft hand feel, and no impact on the functionality of the fabric. It can be widely applied to the dirty washing style processing of garments made of natural fibers such as cotton, linen, silk, and wool, as well as regenerated cellulose fibers such as viscose, lyocell, modal, bamboo viscose fiber, and cupro fiber.

[0060] The descriptions and practices disclosed in this invention are readily apparent and understandable to those skilled in the art, and various modifications and refinements can be made without departing from the principles of this invention. Therefore, any modifications or improvements made without departing from the spirit of this invention should also be considered within the scope of protection of this invention.

Claims

1. A processing method for preparing garments with a sand-dyed and dirty wash style, characterized in that, Includes the following steps: Step 1, Pretreatment: The garment is desized and scouring to remove impurities and improve the hygroscopicity and reactivity of the fibers; Step 2, Leuco preparation: Add the reducible dye to an aqueous solution containing a reducing agent and an alkali to reduce it to a soluble leuco sodium salt; Step 3, dyeing: Immerse the pretreated garment in the leuco dye solution for dyeing, or apply the leuco dye solution to the garment by spraying. Step 4, Liquid uniformity: After dyeing, control the liquid content of the garment to be between 30% and 150%, and rotate it in a rotating drum at a speed of 8-15 r / min for 3-30 minutes, while maintaining the temperature at 25-60℃ and the pH value between 10-14, so that the leuco pigment is evenly distributed inside the garment fibers. Step 5, Oxidation and Color Development: Expose the homogenized garment to air for oxidation, or use an oxidizing agent for oxidation; Step 6, Washing and softening: Wash and soften the oxidized garments. Step 7, Finishing: After softening, the garment is dehydrated, dried and shaped to obtain a garment with a sand-dyed and dirty wash style.

2. The processing method for preparing a garment with a sand-dyed and dirty-washed style according to claim 1, characterized in that, In step 4, at least one of a leveling agent and a reducing agent supplement is added during the homogenization process; the amount of the leveling agent is 0.5~5g / L, and the amount of the reducing agent supplement is 5%~10% of the weight of the vat dye.

3. The processing method for preparing a garment with a sand-dyed and dirty-washed style according to claim 2, characterized in that, In step 4, an anti-migration agent is added during the homogenization process, with a dosage of 1-10 g / L.

4. The processing method for preparing a garment with a sand-dyed and dirty-washed style according to claim 1, characterized in that, In step 5, the oxidation method also includes in-situ oxidation during the drying process: the homogenized garment is dried in a rotary drum at 60~110℃ for 5~60 minutes, so that the leuco pigment oxidizes during the drying process.

5. The processing method for preparing a garment with a sand-dyed and soiled wash style according to claim 1, characterized in that, Steps 1 to 7 employ a soaking-dehydration-drying method, specifically as follows: Immerse the pretreated garments in leuco dye solution at 25-60℃ for 5-30 minutes; Dehydrate the soaked garments until the liquid content is 45%-150%; After dehydration, the garment is rotated in a drum at 8-10 r / min for 5-30 minutes to homogenize the liquid. After homogenization, the garment is dried in a rotary drum at 60-110℃ for 5-60 minutes to allow the leuco pigment to oxidize during the drying process. The dried garments are then washed, softened, and finished.

6. The processing method for preparing a garment with a sand-dyed and dirty-washed style according to claim 1, characterized in that, Steps 1 to 7 employ the spray-homogenization-heating method, specifically as follows: The pre-treated garments are placed in a rotating drum and rotated at a speed of 10-15 r / min; The leuco dye solution is evenly sprayed onto the garment using a spray method, with the liquid retention rate controlled between 30% and 150%. Continue rotating at 10-15 r / min for 5-30 minutes to homogenize the liquid; Heat the rotating drum to 60-110℃ and rotate it for 5-60 minutes to allow the leuco form to oxidize during the heating process. The oxidized garments are then washed, softened, and finished.

7. The processing method for preparing a garment with a sand-dyed and dirty wash style according to claim 1, characterized in that, The reducible dye is selected from one or more of the following: sulfur, indigo, anthraquinone, indigo group, or polycyclic reducible dyes.

8. A garment with a sand-dyeing and dirty-wash style, characterized in that, It is prepared by the processing method described in any one of claims 1-7.

9. A garment with a sand-dyeing and dirty-wash style according to claim 8, characterized in that, The garments are made of natural fibers such as cotton, linen, silk, and wool, as well as regenerated cellulose fibers such as viscose, lyocell, modal, bamboo viscose fiber, cupro fiber, and regenerated cellulose fiber.