A dyeing method and a dyeing apparatus

Abstract

This invention discloses a dyeing method and apparatus, relating to the field of fabric dyeing. The dyeing apparatus of this invention includes, sequentially arranged along the fabric conveying direction, a drying chamber, a cooling device, a humidifying device, a heating chamber, and a dyeing tank. The drying chamber is used to dry the fabric; the cooling device is used to cool the fabric to room temperature; the humidifying device is used to humidify the fabric to a set value; the heating chamber is used to heat the humidified fabric; and the dyeing tank is used to dye the fabric. This invention, by sequentially setting drying, cooling, humidifying, and heating processes before the fabric enters the dyeing tank, first thoroughly dries the fabric to eliminate uneven moisture content inherent in the incoming fabric, then cools it to room temperature for uniform humidification, and finally heats it to a higher temperature. This ensures that the fabric has a consistent moisture content and temperature when entering the dyeing tank, effectively avoiding dyeing defects such as color difference, edge-to-center difference, and localized color variations caused by differences in the moisture content of the incoming fabric, significantly improving dyeing uniformity and product quality.

Description

Technical Field

[0001] This invention relates to the field of fabric dyeing, and in particular to a dyeing method and dyeing apparatus. Background Technology

[0002] During the fabric processing, the semi-finished product needs to be dyed to produce fabrics of different colors. The general method of fabric dyeing is to directly send the material into the dyeing tank for immersion and dyeing. After the immersion and dyeing are completed, the material is dried, cured and shaped.

[0003] To improve the uniformity and dyeing effect of fabrics during dyeing in the dyeing tank, pretreatment is often performed on the fabrics before they enter the dyeing tank. Existing pretreatment generally includes humidifying the fabrics first, then heating them after humidification, and finally sending the fabrics into the dyeing tank. This method of humidifying first and then heating utilizes humidification to make the fibers in the fabrics swell first, which increases the micro-gaps in the amorphous region, making it easier for dye molecules to enter the dyeing tank and reach the core layer directly from the fiber surface, thus achieving through dyeing.

[0004] However, in actual production, for fabrics made of heavy-duty glass fiber / aramid / microfiber layers, if the incoming fabric has extremely uneven moisture content, simple surface spraying / steam spraying for humidification will cause moisture to easily bead, slide, and drop at local water-repellent points or wet-dry boundaries on the fabric surface. This prevents the humidifying water from penetrating evenly into the fiber network, instead amplifying the originally hidden moisture content differences into visible water spots, streaks, and cloudiness. Even after heating and raising the temperature before being sent to the dyeing bath, the wet area will heat up later due to evaporation and heat absorption, while the dry area will heat up faster, creating microscale temperature and adsorption rate differences on the fabric surface. The dye will undergo uneven primary adsorption at these locations, and the subsequent heat preservation stage will also be difficult to completely balance, ultimately resulting in color difference, edge-to-center difference, and local color variations. Summary of the Invention

[0005] This invention provides a dyeing method and dyeing apparatus, which can solve the problems of color difference, edge-to-center difference and local color spots that are easily caused by directly sending the fabric with low moisture content into the dyeing bath after rehydration and heating in the prior art.

[0006] A dyeing apparatus comprises, in sequence along the fabric conveying direction, a drying chamber, a cooling device, a humidifying device, a heating chamber, and a dyeing tank; the drying chamber is used to dry the fabric; the cooling device is used to cool the fabric to room temperature; the humidifying device is used to humidify the fabric to a set value; the heating chamber is used to heat the humidified fabric to increase its temperature; and the dyeing tank is used to dye the fabric.

[0007] Furthermore, the drying chamber includes a box body with first narrow slits at both ends. The top and bottom of the box body are respectively provided with a plurality of exhaust structures and a plurality of air inlet structures along the fabric conveying direction. The air inlet structures are connected to a heating chamber. The air inlet end of the heating chamber is connected to a negative pressure device. Temperature sensor 1, heater and temperature sensor 2 are arranged sequentially along the airflow direction inside the heating chamber. Temperature sensor 1, heater and temperature sensor 2 are all connected to a microprocessor.

[0008] Furthermore, the cooling device includes a box body II with second narrow slits at both ends. The top and bottom of the box body II are respectively provided with a plurality of exhaust structures II and a plurality of air intake structures II along the fabric conveying direction. The exhaust structures II are connected to a negative pressure device I, and a filter is detachably installed at the air intake structures II.

[0009] Furthermore, the humidification device includes a box body three with third narrow slits at both ends. A partition one and a partition two are respectively provided on the top and bottom sides of the box body three. The partition one is located directly above the partition two, and a channel for fabric to pass through is formed between the two. The height of the channel is between 0.15 cm and 0.5 cm. The box body three is divided into an upper humidification area and a lower humidification area by the partition one and partition two. An air inlet structure threeA and an exhaust structure threeA are sequentially provided at the top and bottom of the box body three within the upper humidification area. An exhaust structure threeB and an air inlet structure threeB are sequentially provided at the top and bottom of the box body three within the lower humidification area. The air inlet structure threeB and air inlet structure threeA are connected to the atomizing humidification chamber, and the exhaust structure threeA and exhaust structure threeB are connected to the negative pressure device two.

[0010] Furthermore, the upper humidification zone and the lower humidification zone are arranged sequentially along the fabric conveying direction;

[0011] The first partition forms an obtuse angle α with the direction of fabric travel, and the second partition forms an obtuse angle β with the direction of fabric travel.

[0012] Furthermore, the outer wall of the partition is wrapped with absorbent cotton, and the partition is provided with a heating channel or a heating resistance wire; or a water receiving trough is provided at the bottom of the partition.

[0013] Furthermore, the heating box is a box body four with fourth narrow slits at both ends. The box body four is divided into a preheating section and a uniform temperature section along the fabric conveying direction, and the two sections are separated by a heat insulation partition. The heat insulation partition has a sixth narrow slit that allows only the fabric to pass through. The preheating section includes a set of slit-type steam nozzles set at the top and bottom of the box body four. The nozzles face the upper and lower surfaces of the fabric, and the nozzles form an angle of 30°-60° with the normal of the fabric in the spray direction. The uniform temperature section includes infrared radiation heating plates set at the top and bottom of the box body four. The wavelength of the infrared radiation heating plates is 2.5–4.0 μm, and the power density is 0.5–2.0 W / cm².

[0014] Furthermore, the dyeing pool includes a pool body, and several partition plates are arranged along its length inside the pool body. The partition plates have a double-layer structure with heat insulation material filling the middle. A fifth narrow slit is opened on the partition plates for the fabric to pass through only. A set of guide rollers arranged vertically and horizontally along the fabric conveying direction is arranged inside the pool body.

[0015] A staining method, wherein the staining steps of the staining method include:

[0016] Step 1: Control the fabric to dry in the drying box;

[0017] Step 2: Send the dried fabric into a cooling device for cooling treatment;

[0018] Step 3: Send the cooled fabric into a humidification device for humidification treatment;

[0019] Step 4: Place the humidified fabric into the heating chamber for preheating treatment;

[0020] Step 5: Send the preheated fabric into the dyeing tank for dyeing treatment.

[0021] Step 6: Pre-dry, bake, and shape the dyed fabric in sequence.

[0022] Furthermore, the moisture content of the fabric after the drying process in step 1 is ≤10%;

[0023] After the cooling process in step 2, the temperature of the fabric is below 30°C.

[0024] The moisture content of the fabric after the humidification treatment in step 3 is between 20% and 40%.

[0025] The temperature of the fabric after preheating in step 4 is T1, and the temperature of the dye liquor at the inlet of the dyeing pool is T2. Then, T1 + T3 = T2, where T3 is the preset temperature difference compensation value before the fabric enters the dyeing pool, which is between 3℃ and 8℃.

[0026] When the fabric is cotton and the dye is reactive, T1 is 37℃-40℃ and T2 is 40℃-48℃; when the fabric is polyester and the dye is disperse, T1 is 50℃-55℃ and T2 is 53℃-63℃.

[0027] The present invention has the following beneficial effects:

[0028] 1. This invention sets up drying, cooling, humidifying and heating processes in sequence before the fabric enters the dyeing tank. First, the fabric is thoroughly dried to eliminate the problem of uneven moisture content in the incoming fabric. Then, it is cooled to room temperature and humidified evenly. Finally, it is heated to ensure that the fabric has a consistent moisture content and temperature when it enters the dyeing tank. This effectively avoids dyeing defects such as color difference, edge-to-center difference and local color spots caused by differences in the moisture content of the incoming fabric, and significantly improves dyeing uniformity and product quality.

[0029] 2. The present invention uses a pretreatment sequence of humidification followed by heating to allow the fabric fibers to fully swell in a moist state, increasing the micropores in the amorphous region of the fibers. Then, heating is used to raise the temperature so that the fibers reach a suitable absorption temperature, which is conducive to the penetration of dye molecules from the fiber surface to the core, achieving a through-dyeing effect and improving the dye uptake rate and dyeing depth.

[0030] 3. The present invention uses a cooling device to cool the dried fabric to room temperature before humidification, which avoids the violent condensation and water droplet accumulation caused by the direct contact of the high-temperature fabric with the humidification mist droplets, ensuring the stability and controllability of the humidification process, reducing rework and scrap rates caused by process fluctuations. At the same time, the entire device is continuously arranged along the fabric conveying direction, realizing automated assembly line operation and improving production efficiency. Attached Figure Description

[0031] Figure 1 Schematic diagram of the staining apparatus provided by the present invention Figure 1 ;

[0032] Figure 2 Schematic diagram of the staining apparatus provided by the present invention Figure 2 ;

[0033] Figure 3 This is a schematic diagram of the drying box structure provided by the present invention;

[0034] Figure 4 This is a schematic diagram of the cooling device structure provided by the present invention;

[0035] Figure 5 This is a schematic diagram of the humidification device provided by the present invention;

[0036] Figure 6 This is a schematic diagram of the heating box structure provided by the present invention;

[0037] Figure 7 This is a schematic diagram of the staining pool structure provided by the present invention.

[0038] Explanation of reference numerals in the attached figures:

[0039] 100-Fabric, 1-Drying box, 10-Box body one, 11-Exhaust structure one, 12-Intake structure one, 13-Heating chamber, 14-Negative pressure device one, 2-Cooling device, 20-Box body two, 21-Exhaust structure two, 22-Intake structure two, 3-Humidifying device, 30-Box body three, 301-Partition one, 302-Partition two, 31-Intake structure threeA, 32-Exhaust structure threeA, 33-Exhaust structure threeB, 34-Intake structure threeB, 4-Heating box, 40-Box body four, 41-Insulation partition, 42-Nozzle, 43-Infrared radiation heating plate, 5-Dyeing pool, 50-Pool body, 51-Divider plate, 52-Fifth narrow slit, 53-Guide roller group. Detailed Implementation

[0040] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0041] To overcome the technical problem mentioned in the background art, where uneven moisture content in the fabric leads to water spots and streaks after humidification, resulting in uneven dyeing, such as... Figures 1 to 2 As shown in the figure, an embodiment of the present invention provides a dyeing apparatus, which includes a drying box 1, a humidifying device 3, a heating box 4 and a dyeing pool 5 arranged sequentially along the conveying direction of the fabric 100.

[0042] The drying box 1 is used to thoroughly dry the fabric 100; the humidifying device 3 is used to humidify the fabric 100 to a set value; the heating box 4 is used to heat the humidified fabric 100 to raise its temperature; and the dyeing tank 5 is used to dye the fabric 100.

[0043] It is understood that the technical solution of humidifying first and then heating in this invention is referred to as Scheme 1, while the technical solution of heating first and then humidifying is referred to as Scheme 2.

[0044] For wool / silk, Option 1, humidifying first, can prevent the protein fibers from denaturing, yellowing, and becoming brittle under dry heat. After humidification, the fibers become soft, and the subsequent heating temperature can be reduced. Option 2, dry heat, directly acts on the protein fibers, which can easily cause irreversible damage.

[0045] For polyester / aramid / carbon fiber, the fiber surface is inert. Option 1 is to activate the surface by humidifying or carrying a treatment liquid, and then heating to promote a chemical reaction. Option 2 is that dry heat cannot change the surface inertness, and humidification only stays on the surface and cannot penetrate.

[0046] For microfiber / island-sea yarn, microfiber has a large specific surface area and is prone to static electricity and fuzzing under dry heat. Solution 1: Humidification can eliminate static electricity and loosen the fiber bundles. Solution 2: Dry heat aggravates static electricity, causes fiber entanglement, and results in uneven dyeing.

[0047] Furthermore, the specific heat capacity of a wet cloth with 30% water content is twice that of a dry cloth, and its temperature rises slowly and controllably in the heating chamber. Because the dry cloth is humidified after being heated, the temperature of the dry cloth will drop. Since the humidification may be uneven, this will lead to uneven temperature in different parts of the dry cloth, and it is inconvenient to control.

[0048] To avoid the problem of rapid evaporation or uneven penetration of moisture caused by direct humidification of high-temperature fabric, a cooling device 2 is also installed between the drying chamber 1 and the humidification equipment 3. The cooling device 2 is used to cool the dried fabric 100 to room temperature.

[0049] To achieve efficient and controllable drying, such as Figure 3 The drying chamber 1 includes a chamber body 10 with first narrow slits at both ends; the top and bottom of the chamber body 10 are respectively provided with a plurality of exhaust structures 11 and a plurality of air inlet structures 12 along the conveying direction of the fabric 100; the air inlet structure 12 is connected to a heating chamber 13, and the air inlet end of the heating chamber 13 is connected to a negative pressure device 14; temperature sensor 1, heater and temperature sensor 2 are arranged sequentially along the airflow direction inside the heating chamber 13, and temperature sensor 1, heater and temperature sensor 2 are all connected to a microprocessor; through the negative pressure device 14, external air is heated by the heating chamber 13 and then evenly blown onto the fabric by the air inlet structure 12. Hot air passes through the fabric and is discharged through exhaust structure 11, forming an airflow that vertically penetrates the fabric 100. When this hot air passes through the fabric 100, it can quickly remove the residual moisture in the fabric 100, improving the drying efficiency. At the same time, through the setting of microprocessor, temperature sensor 1, heater and temperature sensor 2, the temperature at the air outlet and air inlet is detected by temperature sensor 2 and temperature sensor 1 respectively, realizing feedback control of the heating power of the heater, ensuring the stability of the air outlet temperature, thereby reliably reducing the moisture content of the fabric 100 to below 5%, creating a uniform starting point for subsequent uniform humidification.

[0050] To achieve efficient cooling and prevent secondary contamination, such as Figure 4The cooling device 2 includes a box 20 with second narrow slits at both ends. The top and bottom of the box 20 are respectively provided with several exhaust structures 21 and several air inlets 22 along the fabric 100 conveying direction. The exhaust structures 21 are connected to a negative pressure device 14. Through the negative pressure device 14, cold air is drawn in from the air inlets 22, passes through the high-temperature fabric 100, and is discharged from the exhaust structures 21, quickly carrying away heat. Simultaneously, a filter is detachably installed at the air inlets 22 to effectively filter dust from the air, preventing dust contamination of the fabric 100. The high-temperature gas discharged from the exhaust structures 21 enters the heating chamber 13 to recover waste heat and reduce the energy consumption of the heating chamber 13.

[0051] To address the core problem in the background technology of uneven humidification caused by simple spray / steam spraying, resulting in water spots and streaks, such as... Figure 5 The humidification device 3 of the present invention includes a box body 30 with third narrow slits at both ends. A partition 301 and a partition 302 are respectively provided on the top and bottom sides of the box body 30. The partition 301 is located directly above the partition 302, and a channel for the fabric 100 to pass through is formed between the two. The height of the channel is between 0.15cm and 0.5cm. The box body 30 is divided into an upper humidification area and a lower humidification area by the partitions 301 and 302. The upper and lower humidification areas are arranged sequentially along the conveying direction of the fabric 100. An air inlet structure 3A31 and an exhaust structure 3A32 are sequentially provided at the top and bottom of the box body 30 in the upper humidification area. An exhaust structure 3B33 and an air inlet structure 3B34 are sequentially provided at the top and bottom of the box body 30 in the lower humidification area. Intake structures 3B34 and 3A31 are connected to the atomizing humidification chamber, and exhaust structures 3A32 and 3B33 are connected to the negative pressure device 2; therefore, an airflow from top to bottom is formed in the upper humidification area, which passes through the fabric 100 from top to bottom; at the same time, an airflow from bottom to top is formed in the lower humidification area, which passes through the fabric 100 from bottom to top.

[0052] In other words, this invention uses a top-down and bottom-up airflow layout, combined with the negative pressure effect of the negative pressure device 2, to enable the atomized water vapor to penetrate the fabric 100 powerfully from both the top and bottom directions, avoiding the uneven wetting caused by traditional single-sided spraying and completely eliminating the generation of water spots and streaks.

[0053] Meanwhile, in this invention, if the order of the upper humidification area and the lower humidification area is reversed, that is, when the fabric 100 enters the box 30, it first passes through the lower humidification area and then enters the upper humidification area, the lower surface of the fabric 100 is first humidified by the lower spray, and then the upper surface of the fabric 100 is humidified by the upper spray after entering the upper humidification area; in this way, the lower surface of the fabric preferentially absorbs water, the fibers begin to swell, the pores decrease, and the air permeability decreases. When the fabric subsequently enters the upper humidification zone, the downward airflow needs to penetrate the partially moistened and shrunken fabric, significantly increasing the penetration resistance. The atomized water vapor struggles to reach the deeper layers of the upper surface, resulting in a much lower humidification level on the upper surface compared to the lower surface. This creates an asymmetry in moisture content between the upper and lower surfaces, leading to noticeable color differences between the two sides during subsequent dyeing. This invention employs a top-humidification followed by a bottom-humidification approach. Although the upper surface of the fabric preferentially absorbs the atomized water vapor after top humidification, and the pores shrink after fiber swelling, the lower layer of fabric 100 remains dry, with unswollen fibers and normal pores. Subsequently, the upward airflow enters from the dry lower surface. Although the upper layer of fabric 100 has swelled, its pores have only shrunk, not completely closed. Furthermore, since both the airflow direction and the direction of the swollen layer are from bottom to top, the airflow can still squeeze through the shrunken pores to reach the upper surface. In addition, the upper surface is already moistened, reducing the need for moisture, which actually facilitates the transfer of moisture to the lower surface, achieving uniform humidification overall. This is equivalent to stacking two sponges together. If you wet the top part first while the bottom part remains dry, water can seep upwards from the bottom. However, if you wet the bottom part first, it will expand and block the channels at the top, making it difficult for water to seep downwards from the top.

[0054] In this invention, partition 1 301 forms an obtuse guiding angle α with the direction of travel of fabric 100, and partition 2 302 forms an obtuse guiding angle β with the direction of travel of fabric 100. The inclined arrangement of partition 1 301 and partition 2 302 avoids crossflow of gas between the upper humidification area and the lower humidification area, that is, it guides the airflow from top to bottom in the upper humidification area and the airflow from bottom to top in the lower humidification area.

[0055] To prevent condensation on partition 301 from dripping onto fabric 100 and causing secondary pollution, the outer wall of partition 301 is wrapped with absorbent cotton, and a heating channel or heating resistance wire is provided inside partition 301. The heating channel or heating resistance wire can keep partition 301 at a relatively high temperature, thus preventing condensation of the humidified atomized water on partition 301.

[0056] Alternatively, a water collection trough may be provided at the bottom of partition 301. The water collection trough is located on the surface of partition 301 close to the fabric 100. When condensation occurs on the surface of partition 301, the water droplets will slide down the surface of partition 301 under the action of gravity and drip into the water collection trough for collection. At the same time, a drain pipe can be connected to the water collection trough and penetrate the side wall of box 30. The drain pipe and the side wall of box 30 are sealed with sealant.

[0057] After humidification, preheating is necessary to ensure the fibers absorb dye at the optimal temperature. Heating chamber 4 is used to heat the humidified fabric 100. To achieve gentle, uniform, and efficient preheating, and to avoid uneven secondary moisture distribution caused by excessively rapid heating; Figure 6 The heating chamber 4 is a box 40 with a fourth narrow slit at both ends. The interior of the box 40 is divided into a preheating section and a uniform temperature section along the conveying direction of the fabric 100, separated by a heat-insulating partition 41. The heat-insulating partition 41 has a sixth narrow slit that allows only the fabric 100 to pass through. The preheating section includes a set of slit-type steam nozzles 42 at the top and bottom of the box 40. The nozzles 42 face the upper and lower surfaces of the fabric 100, and the nozzles 42 form an angle of 30°-60° with the normal of the fabric 100 in the direction of spray. This angle design allows the saturated steam to impact the fabric 100 at a gentle angle, quickly and evenly transferring heat to the interior of the fabric 100 fibers without disrupting the already formed uniform water film. Subsequently, the fabric enters the uniform temperature section, which includes infrared sensors located at the top and bottom of the box 40. The infrared radiation heating plate 43 has a wavelength of 2.5-4.0μm and a power density of 0.5-2.0W / cm2. The infrared radiation matches the vibration frequency of water molecules and can be efficiently absorbed by water-containing fibers, achieving uniform heating from the inside out. This further bridges the small temperature difference, ensuring that the temperature T1 of the fabric 100 and the temperature T2 of the dye bath at the feed end satisfy the relationship: T1+T3=T2, where T3 is between 3℃ and 8℃. This means that the temperature of the fabric 100 is slightly lower than that of the dye bath, thus avoiding color variations caused by instantaneous high-temperature fixation.

[0058] The nozzle 42 above the fabric 100 forms an acute angle with the fabric 100 conveying direction in the spraying direction, while the nozzle 42 below the fabric 100 forms an obtuse angle with the fabric 100 conveying direction in the spraying direction. The steam ejected from the upper nozzle 42, tilted forward, applies a forward thrust along the fabric 100's forward movement, helping to smoothly convey the fabric 100 and preventing wrinkles caused by tension fluctuations. The lower nozzle 42, tilted backward, ejects steam that impacts upward and backward, creating a backward thrust and an upward lift on the lower surface of the fabric 100. This causes the fabric 100 to be slightly suspended, reducing contact friction with the supporting structure below and preventing scratches or drag marks on the already wetted fabric 100 surface.

[0059] The upper and lower nozzles 42 are oriented in opposite directions, forming a pair of shearing airflows in the thickness direction of the fabric 100. This shearing action forces the steam to flow laterally in the fiber gaps, promoting the penetration of steam from the upper and lower surfaces into the core of the fabric 100 and improving heating uniformity. At the same time, the oblique injection avoids the vertical impact of steam on the surface of the fabric 100, which would cause the water film to break or splash, thus protecting the uniform water film formed during the humidification stage. Furthermore, the upper and lower nozzles 42 are oriented in opposite directions, so that when the two steam jets meet at the fabric 100, they will not directly collide and cancel each other out. This helps to establish a stable temperature and humidity field throughout the preheating section and avoids temperature differences caused by local eddies.

[0060] The preheated fabric 100 is then placed in dyeing tank 5 for dyeing. To ensure the stability and uniformity of the dyeing process, such as... Figure 7 The dyeing pool 5 includes a pool body 50. Several partition plates 51 are arranged along the length of the pool body 50. The partition plates 51 have a double-layer structure and are filled with heat insulation material in the middle. A fifth narrow slit 52 is opened on the partition plate 51 for the fabric 100 to pass through only. A set of guide rollers 53 arranged vertically and vertically along the conveying direction of the fabric 100 is arranged in the pool body 50. The dyeing pool 5 is divided into a low temperature adsorption zone with a temperature of 50°C, a medium temperature penetration zone with a temperature of 80°C, and a high temperature fixing zone with a temperature of 120°C along the conveying direction of the fabric 100 by the two partition plates 51.

[0061] In the low-temperature adsorption zone, the disperse dye is initially adsorbed on the polyester surface; in the medium-temperature penetration zone, the temperature reaches the glass transition temperature, at which point the fiber molecular chain segments begin to move, the free volume increases, and the dye begins to diffuse into the interior; in the high-temperature fixation zone, the disperse dye completes its migration and fixation into the fiber interior.

[0062] It is understood that in this invention, the air intake structure 12, air intake structure 22, air intake structure 3A32 and air intake structure 3B34 have the same structure, all including a horizontal pipe 1. The side wall of the horizontal pipe 1 is provided with air jet holes in the axial direction, and the length direction of the horizontal pipe 1 is perpendicular to the conveying direction of the fabric 100.

[0063] It is known that in this invention, exhaust structure 11, exhaust structure 21, exhaust structure 3A33, and exhaust structure 3B33 have the same structure, all including a horizontal pipe 2. The side wall of the horizontal pipe 2 is provided with an air intake hole in the axial direction. A horn-shaped air intake cover is installed on the air intake hole, and the length direction of the horizontal pipe 2 is perpendicular to the conveying direction of the fabric 100.

[0064] Based on the above-described apparatus, the present invention also provides a staining method, comprising the following steps:

[0065] Step 1: Control the fabric 100 to be dried in the drying box 1 to make its moisture content ≤5%.

[0066] Step 2: Send the dried fabric 100 into the cooling device 2 for cooling treatment so that its temperature is below 30℃.

[0067] Step 3: The cooled fabric 100 is sent into the humidification device 3 for humidification treatment, so that the moisture content of the fabric 100 reaches 25%.

[0068] Step 4: Send the humidified fabric 100 into the heating box 4 for preheating treatment, so that the temperature of the preheated fabric reaches 47℃.

[0069] Step 5: Send the preheated fabric 100 into the dyeing tank 5 for dyeing treatment.

[0070] Step 6: Pre-dry, bake and shape the dyed fabric 100 in sequence.

[0071] The above methods fundamentally solve the dyeing quality problem caused by uneven moisture content in the fabric, achieving a high-quality and highly uniform dyeing effect.

[0072] The polyester fabric 100 is dyed using a dyeing method. First, it is dried to remove uncontrollable moisture absorbed during the production, storage, and transportation of the polyester fabric. It is then cooled to room temperature to avoid the hot fabric (above 50°C) directly entering the humidification device 3. When the humidification droplets come into contact with the fabric surface of the fabric 100, some of the moisture will evaporate immediately instead of being absorbed by the fibers. This not only reduces the actual humidification efficiency but also causes the moisture content at the outlet of the humidification device 3 to become unstable. By lowering the fabric temperature to room temperature, the evaporation loss during the humidification process is minimized, the humidification efficiency is close to 100%, and the moisture content has a linear relationship with the humidification amount, making it easy to control precisely.

[0073] If a hot fabric above 90°C is directly introduced into the humidification device 3, the room-temperature mist droplets will undergo intense local condensation upon encountering the high-temperature fabric surface, forming large condensed water droplets instead of uniform, tiny mist droplets. These condensed water droplets roll and converge on the fabric surface, forming water spots (locally over-humidified areas), while areas not covered by water droplets will be under-humidified. If the fabric 100 enters the subsequent heating chamber 4 and dyeing tank 5 in this state, it will directly lead to uneven coloring, stripes, and edge-to-center differences. Lowering the fabric temperature to near room temperature will prevent intense condensation when the humidification mist droplets come into contact with the fabric surface, instead allowing them to be evenly distributed on the fiber surface through adsorption, thus ensuring the spatial uniformity of humidification.

[0074] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A dyeing apparatus, characterized in that, Along the fabric (100) conveying direction, a drying box (1), a cooling device (2), a humidifying device (3), a heating box (4) and a dyeing pool (5) are arranged in sequence; The drying box (1) is used to dry the fabric (100); The cooling device (2) is used to cool the fabric (100) to room temperature; The humidification device (3) is used to humidify the fabric (100) to a set value; The heating box (4) is used to heat the humidified fabric (100) to increase its temperature; The dyeing pool (5) is used to dye the fabric (100); The humidification device (3) includes a box body three (30) with a third narrow slit at both ends. The top side and bottom side of the box body three (30) are respectively provided with a partition one (301) and a partition two (302). The partition one (301) is located directly above the partition two (302), and a channel for the fabric (100) to pass through is formed between the two. The height of the channel is between 0.15 cm and 0.5 cm. The interior of the housing 3 (30) is divided into an upper humidification area and a lower humidification area by partition 1 (301) and partition 2 (302); An air intake structure 3A (31) and an exhaust structure 3A (32) are sequentially provided at the top and bottom of the box 3 (30) located in the upper humidification area. The top and bottom of the box three (30) located in the lower humidification area are provided with an exhaust structure three B (33) and an air intake structure three B (34) in sequence. The air intake structure 3B (34) and air intake structure 3A (31) are connected to the atomizing humidification chamber, and the exhaust structure 3A (32) and exhaust structure 3B (33) are connected to the negative pressure device 2. The upper humidification area and the lower humidification area are arranged sequentially along the fabric (100) conveying direction. The first partition (301) forms an obtuse angle α with the direction of travel of the fabric (100), and the second partition (302) forms an obtuse angle β with the direction of travel of the fabric (100).

2. The staining apparatus as described in claim 1, characterized in that, The drying box (1) includes a box body (10) with first narrow slits at both ends. The top and bottom of the box body (10) are provided with a plurality of exhaust structures (11) and a plurality of air intake structures (12) along the fabric (100) conveying direction, respectively. The air intake structure (12) is connected to a heating chamber (13). The air intake end of the heating chamber (13) is connected to a negative pressure device (14). Temperature sensor one, heater and temperature sensor two are arranged sequentially in the heating chamber (13) along the airflow direction. Temperature sensor one, heater and temperature sensor two are all connected to a microprocessor.

3. The staining apparatus as described in claim 2, characterized in that, The cooling device (2) includes a box body two (20) with second narrow slits at both ends. The top and bottom of the box body two (20) are respectively provided with a plurality of exhaust structures two (21) and a plurality of air intake structures two (22) along the fabric (100) conveying direction. The exhaust structure two (21) is connected to a negative pressure device one (14). A filter is detachably installed at the air intake structure two (22).

4. The staining apparatus as described in claim 1, characterized in that, The outer wall of the partition (301) is wrapped with absorbent cotton, and the partition (301) is provided with a heating channel or a heating resistance wire. Alternatively, a water receiving trough may be provided at the bottom of the partition (301).

5. The staining apparatus as described in claim 1, characterized in that, The heating box (4) is a box body four (40) with a fourth narrow slit at both ends. The box body four (40) is divided into a preheating section and a uniform temperature section in sequence along the conveying direction of the fabric (100). The two sections are separated by a heat insulation partition (41). The heat insulation partition (41) has a sixth narrow slit that allows only the fabric (100) to pass through; The preheating section includes a set of slit steam nozzles (42) set at the top and bottom of the four (40) boxes. The nozzles (42) face the upper and lower surfaces of the fabric (100), and the nozzles (42) are at an angle of 30°-60° to the normal of the fabric (100) in the direction of spraying. The temperature equalization section includes infrared radiation heating plates (43) set at the top and bottom of the four (40) boxes. The infrared radiation heating plates (43) have a wavelength of 2.5–4.0 μm and a power density of 0.5–2.0 W / cm².

6. The staining apparatus as described in claim 1, characterized in that, The dyeing pool (5) includes a pool body (50), and a plurality of partition plates (51) are arranged inside the pool body (50) along its length. The partition plates (51) have a double-layer structure and are filled with heat insulation material in the middle. The partition plate (51) has a fifth narrow slit (52) for the fabric (100) to pass through only, and the pool body (50) has a set of guide rollers (53) arranged in an alternating manner along the fabric (100) conveying direction.

7. A staining method, characterized in that, The staining method is based on a staining apparatus according to any one of claims 1-6, and the staining steps include: Step 1: Control the fabric (100) to be dried in the drying box (1); Step 2: Send the dried fabric (100) into the cooling device (2) for cooling treatment; Step 3: Send the cooled fabric (100) into the humidification equipment (3) for humidification treatment; Step 4: Place the humidified fabric (100) into the heating box (4) for preheating treatment; Step 5: Send the preheated fabric (100) into the dyeing tank (5) for dyeing treatment; Step 6: Pre-dry, bake and shape the dyed fabric (100) in sequence.

8. The staining method as described in claim 7, characterized in that, After the drying process in step 1, the moisture content of the fabric (100) is ≤10%; After the cooling treatment in step 2, the temperature of the fabric (100) is below 30°C; The moisture content of the fabric (100) after the humidification treatment in step 3 is between 20% and 40%. The temperature of the fabric (100) after preheating in step 4 is T1, and the temperature of the dye liquor at the feed end of the dyeing pool is T2. Then T1 + T3 = T2, and T3 is the preset temperature difference compensation value before the fabric enters the dyeing pool. The preset temperature difference compensation value is between 3℃ and 8℃.

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