Processing technology for improving ageing color matching of digital printing

Abstract

The invention belongs to the technical field of textile finishing, and particularly relates to a processing technology for improving ageing color matching of digital printing. Comprising the following processes of singeing, desizing and scouring, oxygen bleaching, mercerizing, pre-tentering, tentering and sizing, digital printing, ageing, loose washing, tentering and preshrinking. A feed liquid used in the tentering and sizing process comprises 3-8 g / L of a defoaming agent, 5-10 g / L of anhydrous sodium sulphate, 25-35 g / L of baking soda, 80-150 g / L of urea and 80-120 g / L of ARJ; in the ageing process, a cloth feeding mode comprises double-layer cloth feeding and double-layer tension applying cloth feeding, the ring length of a hanging rod is 1-2 m, the rotating speed of the hanging rod is 12-36 r / h, and the rotating speed of a circulating fan is 20-30 Hz. The method can effectively improve white-ground or light-ground digital printing ageing color matching, so that the appearance of the aged cloth is free of color matching and miscellaneous points, and a high-quality digital printing product can be obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of textile finishing, and in particular relates to a processing technology for improving the steaming and color matching of digital printing. Background Art

[0002] Digital textile printing is a non-contact printing method. The image is output to the printing machine through a computer and printed on the substrate through a nozzle. Cellulose fibers such as cotton, linen, and Tencel and regenerated cellulose fibers are widely used in digital textile printing because of their good wearing comfort and hygroscopicity.

[0003] Chinese invention patent CN107815902A discloses a high-efficiency digital printing process, including the following steps: fabric padding sizing → disperse dye spray printing → drying → steaming → washing → drying; sizing is added and mixed according to the mass ratio of color powder 15-22%, glycerol 20-30%, dispersant 15-25%, resist 10-15%, and water 8-40% to form a slurry. Chinese invention patent CN111535059A discloses a digital printing process for artificial cellulose fiber fabrics, including the following steps: preparing digital printing pretreatment agent → padding pretreatment agent → digital printing spray printing → steaming, washing, and drying; the digital printing pretreatment agent includes the following components by weight: 1-3 parts of paste, 7-25 parts of urea, 0.5-2 parts of printing alkali, 0.5-2 parts of antioxidant, and the balance is water.

[0004] Due to the difference between digital printing and traditional printing, urea, baking soda and thickener cannot be added to ink for inkjet printing. Therefore, digital printing needs to be sizing before printing, followed by printing and steaming. Since the sizing method of digital printing is full-width sizing, the uncolored part also contains sizing. During the steaming process, the fabric becomes more moist after absorbing the saturated steam in the steamer. As the fabric moves and collides with each other in the steamer, the floating color on the surface of the colored part absorbs water and collides with the white or light bottom part, and the white or light bottom part is stained with mixed colors. In the subsequent steaming process, the mixed colors on the white bottom are fixed, which makes it impossible to remove them in the subsequent washing process, resulting in printed fabric defects. The white bottom part of traditional printing does not contain alkali agents and urea. Even if there is a color overlap during the steaming process, the color overlap part can be washed off during the washing process.

[0005] Therefore, in view of the color matching problem that white or light-colored digital printing products in the prior art are prone to occur during the steaming process, it is urgent to develop a process method suitable for cellulose fibers and their blended fabrics, regenerated cellulose fibers and their blended fabrics. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a processing technology for improving the steaming and color matching of digital printing. On the basis of adjusting the steaming process, the sizing process of patterns with larger dark coverage areas is improved, which completely solves the steaming and color matching problem of white-background dark-colored printed varieties, while reducing the generation of defective cloth.

[0007] The technical solution of the present invention is as follows: The processing technology for improving the steaming and color matching of digital printing described in the present invention comprises the following process: singeing → deboiling → oxygen bleaching → mercerizing → pre-stretching → stentering sizing → digital printing → steaming → loose washing → stenting → pre-shrinking.

[0008] Preferably, the liquid used in the stenter sizing process includes 3-8 g / L of defoamer, 5-10 g / L of sodium sulfate, 25-35 g / L of baking soda, 80-150 g / L of urea, and 80-120 g / L of ARJ. The defoamer comes from Jinan Dongsheng Chuangye Chemical Co., Ltd., sodium sulfate comes from Sichuan Xindu Chemical Co., Ltd., baking soda comes from Zibo Weiduo Economic and Trade Co., Ltd., urea comes from Zibo Lifeng Kewo Trading Co., Ltd., and ARJ comes from Giovanni Busset (Shanghai) Chemical Industry and Trade Co., Ltd.; the vehicle speed is 30-50 m / min; and the drying temperature is 80-100°C.

[0009] Preferably, in the steaming process, the steaming temperature is 101-103°C, the steaming time is 10-15min, the hanging rod loop length is 1-2m, the hanging rod speed is 12-36r / h, the hanging rod spacing is 10-20cm, the circulating fan speed is 20-30Hz, and the cloth feeding methods include double-layer cloth feeding and double-layer tension cloth feeding.

[0010] Double-layer cloth feeding: Lay the front printed fabric on a layer of clean guide cloth, so that the printed front is attached to the lining cloth. When looping, the printed parts are not directly in contact, with the guide cloth at the bottom and the printed fabric at the top. Double-layer tension feeding: On the basis of double-layer feeding, tension is added at the feeding end, that is, friction is increased on the upper layer of normal printed fabric during feeding, so that the running speed of the two layers of fabric remains consistent during feeding.

[0011] In the steaming process, when the proportion of dark black patterns on the fabric is ≥60%, the fabric feeding method is double-layer tension feeding. When the proportion of dark black patterns is <60%, the fabric feeding method can be selected as double-layer feeding or double-layer tension feeding according to actual conditions.

[0012] Compared with the prior art, the present invention has the following beneficial effects: The present invention can effectively improve the color matching of white or light-bottom digital printing after steaming, so that the appearance of the steamed cloth has no color matching and spots, and high-quality digital printing products can be obtained.

[0013] (1) In the steaming process, the length of the cloth hanging rod determines the angle of the fabric when it is steamed into a loop. The smaller the length of the hanging rod loop, the larger the fabric loop angle and the smaller the probability of fabric collision. Secondly, the size of the hanging rod rotation speed determines the degree of fabric movement on the hanging rod. The larger the value, the more violent the fabric movement. The hanging rod spacing determines the angle of the fabric when it is steamed into a loop. The larger the hanging rod spacing, the larger the fabric loop angle and the smaller the probability of fabric collision. The present invention adjusts the hanging rod loop length of the steamer steamer to 1-2m, the hanging rod rotation speed to 12-36r / h, the hanging rod spacing to 10-20cm, and the circulating fan speed to 20-30Hz, so that the fabric runs more smoothly in the steamer, effectively reducing the probability of fabric collision during the steaming process of digital printing varieties, and improving the variety of white-bottomed dark-colored printed fabrics.

[0014] (2) In the stenter sizing process, adjust the urea dosage in the slurry to 80-150g / L, so that when the white background and dark printing varieties are steamed, the fabric surface remains in a relatively dry state after absorbing moisture. After the fabrics collide with each other in the steamer, the color matching is reduced due to the dryness of the fabric surface.

[0015] (3) On the basis of double-layer fabric feeding, a tension frame is added to increase the friction of the upper fabric, so that when double-layer fabric is fed, the printed fabric and the guide cloth run more synchronously, greatly reducing the color matching of the printed fabric. DETAILED DESCRIPTION

[0016] The present invention is further described below with reference to the examples. All raw materials used in the examples are commercially available unless otherwise specified.

[0017] Example 1 Fabric specifications: L21×L21×62×56×57 / 58, i.e. pure linen 21 count in warp, pure linen 21 count in weft, warp density 62, weft density 56, width 57-58 inches; 1 / 1 plain weave; Flower type: Dark black flower types account for 10%.

[0018] The processing technology for improving the steaming and color matching of digital printing includes the following processes: singeing → deboiling → oxygen bleaching → mercerizing → pre-stretching → stentering sizing → digital printing → steaming → loose washing → stenting → pre-shrinking.

[0019] (1) Singeing: Strong normal burning, speed 100m / min, flame intensity 20mbar.

[0020] (2) Desizing and boiling: vehicle speed 70 m / min; NaOH 45 g / L; desizing tank temperature 50 °C, desizing pile time 15 min, desizing steamer temperature 100 °C, desizing scraper pressure 0.25 bar; scouring tank temperature 50 °C, scouring pile time 25 min, scouring steamer temperature 100 °C, scouring scraper pressure 0.25 bar; desizing enzyme 3 mL / kg, desizing penetrant 5 mL / kg, desizing refining enzyme 1 mL / kg, desizing extractant 4 mL / kg, scouring refining agent 4 g / L, scouring dewaxing agent 5 mL / kg, scouring penetrant 6 mL / kg, scouring chelating agent 4 mL / kg.

[0021] (3) Oxygen bleaching: vehicle speed 60m / min; pre-wash tank roller pressure 4bar; scraper pressure 0.2bar; piling time 25min; steamer temperature 100℃; 27.5% hydrogen peroxide 10g / L; caustic soda 1g / L; chelating agent 8g / L; penetrant 6g / L; stabilizer 7g / L; 1-4# washing tank temperatures: 95℃ / 95℃ / 95℃ / 90℃ respectively.

[0022] (4) Mercerizing: NaOH 219g / L; caustic soda temperature 50℃; first rolling pressure in the alkali dipping area 4bar; second rolling pressure in the alkali dipping area 4bar; cloth outlet roller pressure 3bar; stable area roller pressure 3bar.

[0023] (5) Pre-stretching: one dip and one roll, water squeeze; speed 50m / min; drying room temperature 110℃.

[0024] (6) Stenter sizing: The liquid used includes 5 g / L defoamer, 5 g / L sodium sulfate, 30 g / L baking soda, 150 g / L urea, and 100 g / L ARJ; the vehicle speed is 30 m / min; and the drying temperature is 90 °C.

[0025] (7) Digital printing: Printing mode: 2-1 feathering 20% ​​unidirectional.

[0026] (8) Steaming: The cloth feeding method is double-layer feeding; the hanging rod ring length is 1.2m, the hanging rod speed is 12r / h, the hanging rod spacing is 10cm, the circulating fan speed is 30Hz, the steaming temperature is 102℃, and the steaming time is 12min.

[0027] (9) Loose water washing: the temperature of the first and second washing tanks is 45°C, the temperature of the third to eighth washing tanks is 95°C, and the temperature of the ninth and tenth washing tanks is 50°C; soap washing liquid RSSLIQ is 9 mL / L; pH is 4.2.

[0028] (10) Stretching: two dips and two rolls, drying room temperature 130°C; vehicle speed 70 m / min; pH-WS: 1 g / L; WA-MZ: 2 g / L; SMI-62: 40 g / L; GS-130: 40 g / L; ECO: 20 g / L.

[0029] (11) Preshrinkage: cloth temperature 35°C; tension 0.3 bar; felt blanket temperature 110°C; rubber blanket temperature 100°C; vehicle speed 60 m / min.

[0030] Example 2 Fabric specifications: CPT60×FFT40(40D)×190×95×55 / 56; 4 / 1 satin; Flower type: Dark black flower types account for 25%.

[0031] The processing technology for improving the color matching of digital printing steaming is described with reference to Example 1, except that: Stenter sizing: the material used includes defoamer 3g / L, sodium sulfate 5g / L, baking soda 25g / L, urea 120g / L, ARJ 80g / L; vehicle speed 40m / min; drying temperature 80℃.

[0032] Steaming: The cloth feeding method is double-layer feeding; the hanging rod ring length is 1m, the hanging rod speed is 24r / h, the hanging rod spacing is 10cm, the circulating fan speed is 30Hz, the steaming temperature is 101℃, and the steaming time is 10min.

[0033] Example 3 Fabric specifications: CM40×SPANDEX40(40D)×120×80×55 / 56; 1 / 1 plain weave; Flower type: Dark black flower types account for 40%.

[0034] The processing technology for improving the color matching of digital printing steaming is described with reference to Example 1, except that: Stenter sizing: the material used includes defoamer 8g / L, sodium sulfate 10g / L, baking soda 35g / L, urea 80g / L, ARJ 120g / L; vehicle speed 50m / min; drying temperature 100℃.

[0035] Steaming: The cloth feeding method is double-layer feeding; the hanging rod ring length is 2m, the hanging rod speed is 36r / h, the hanging rod spacing is 10cm, the circulating fan speed is 20Hz, the steaming temperature is 103℃, and the steaming time is 15min.

[0036] Example 4 Fabric specifications: CM60×SPANDEX60(30D)×150×100×53 / 54; 1 / 1 plain weave; Flower type: Dark black flower types account for 60%.

[0037] The processing technology for improving the color matching of digital printing steaming is described with reference to Example 1, except that: Stenter sizing: the material used includes defoamer 5g / L, sodium sulfate 5g / L, baking soda 30g / L, urea 120g / L, ARJ 100g / L; vehicle speed 30m / min; drying temperature 90℃.

[0038] Steaming: The cloth feeding method is double-layer tension feeding; the hanging rod ring length is 1.2m, the hanging rod speed is 12r / h, the hanging rod spacing is 20cm, the circulating fan speed is 20Hz, the steaming temperature is 102℃, and the steaming time is 12min.

[0039] Comparative Example 1 The fabric specifications are: L21×L21×62×56×57 / 58 (i.e. pure linen 21 count in warp, pure linen 21 count in weft, warp density 62, weft density 56, width 57-58 inches); Organization: 1 / 1 plain weave; Flower type: Dark black flower types account for 10%.

[0040] The processing technology for improving the steaming and color matching of digital printing is described with reference to Example 1, except that: Steaming: the cloth feeding method is single-layer cloth feeding, the back side of the fabric is directly in contact with the hanging rod, and when looping, the front sides of the fabric are opposite.

[0041] Comparative Example 2 Weave specifications: CPT60×FFT40(40D)×190×95×55 / 56, weave: 1 / 4 satin; Flower type: Dark black flower types account for 25%.

[0042] The processing technology for improving the evaporation color matching of digital printing is as described in Example 2, except that 180 g / L of urea is used in the stenter sizing solution.

[0043] Comparative Example 3 Fabric specifications: CM40×SPANDEX40(40D)×120×80×55 / 56; 1 / 1 plain weave; Flower type: Dark black flower types account for 40%.

[0044] The processing technology for improving the steaming and color matching of digital printing is as described in Example 3, except that: steaming: the hanging rod speed is 48r / h, and the circulating fan speed is 40Hz.

[0045] Comparative Example 4 Fabric specifications: CM40×SPANDEX40(40D)×120×80×55 / 56; 1 / 1 plain weave; Flower type: Dark black flower types account for 40%.

[0046] The processing technology for improving the steaming and color matching of digital printing is described with reference to Example 3, except that: Steaming: the length of the hanging rod loop is 3m.

[0047] Comparative Example 5 Fabric specifications: CM60×SPANDEX60(30D)×150×100×53 / 54; 1 / 1 plain weave; Flower type: Dark black flower types account for 60%.

[0048] The processing technology for improving the steaming and color matching of digital printing is described with reference to Example 4, except that the cloth feeding method is double-layer cloth feeding.

[0049] The fabrics processed in Examples 1-4 and Comparative Examples 1-5 were scored for color matching per 100 meters using a four-point scoring method. The results are shown in Table 1. Table 1 100-meter color matching scoring results of the embodiments and comparative examples

[0050] As can be seen from Table 1, compared with Example 1, Comparative Example 1 adopts a single-layer cloth feeding method. Since the fabric enters the steamer through the blowing ring and is hung on the cloth hanging rod in a loop, the front printed parts are in contact with each other, which is easier to form a color match, resulting in a large score. In Comparative Example 2, the amount of urea is too large, resulting in a sharp moisture absorption of the fabric during steaming, and after the fabric absorbs moisture, the fabric moves irregularly in the steamer, resulting in free dye molecules being more likely to stick to the unprinted parts, causing coloring again, and cannot be removed. In Comparative Example 3, the increase in the speed of the hanging rod and the speed of the circulating fan can fully react the dye in the steamer on the one hand, and on the contrary, the increase in the speed of the hanging rod and the speed of the circulating fan makes the fabric move more violently in the steamer, resulting in easier collision between fabrics and fabrics, resulting in color match. In Comparative Example 4, the length of the hanging rod loop increases, the angle of the fabric after looping becomes smaller, and the loop length is longer, making the fabric between each loop easier to collide back and forth, forming a color match. In comparative example 5, no tension was applied during double-layer fabric feeding. Although this could avoid color matching on fabrics with less dark area coverage, when processing fabrics with a larger coverage area, the printed fabric and the guide fabric were offset due to the asynchrony of the double-layer fabric feeding, resulting in irregular color matching.

[0051] In summary, after the fabric is processed by the method of the present invention, the steaming color matching of white or light-bottom digital printing is effectively improved, so that the appearance of the steamed cloth has no color matching and spots, and high-quality digital printing products are obtained. Among them, there is a great improvement in the varieties with white background and dark color printing, and the improvement is more obvious for varieties with a larger dark coverage area.

Claims

1. A processing technology for improving the color matching of digital printing, characterized by: It includes the following processes: singeing → deboiling → oxygen bleaching → mercerizing → pre-stretching → stentering sizing → digital printing → steaming → loose washing → stentering → pre-shrinking; Wherein, the slurry used in the stenter sizing process includes 80-150 g / L of urea; The cloth feeding methods in the steaming process include double-layer cloth feeding and double-layer cloth feeding with tension, the hanging rod loop length is 1-2m, the hanging rod rotation speed is 12-36r / h, and the circulating fan rotation speed is 20-30Hz.

2. The process for improving the color matching of digital printing by steaming according to claim 1, characterized in that: The slurry used in the stenter sizing process also includes 3-8 g / L of defoamer, 5-10 g / L of sodium sulfate, 25-35 g / L of baking soda, and 80-120 / L of ARJ.

3. The process for improving the color matching of digital printing by steaming according to claim 2, characterized in that: The vehicle speed in the stentering sizing process is 30-50 m / min, and the drying temperature is 80-100°C.

4. The process for improving the color matching of digital printing by steaming according to claim 1, characterized in that: In the evaporation process, the evaporation temperature is 101-103° C. and the evaporation time is 10-15 min.

5. The process for improving the color matching of digital printing by steaming according to claim 4, characterized in that: In the steaming process, the spacing between the hanging rods is 10-20 cm.

6. The process for improving the color matching of digital printing by steaming according to claim 5, characterized in that: In the steaming process, when the dark black pattern of the fabric accounts for ≥60%, the fabric feeding method is double-layer tension feeding.

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