Application of digital printing ink based on medium-high reactive group reactive dye

Abstract

The invention discloses application of digital printing ink based on medium-high reactive group reactive dyes, which comprises paste and double-active-group printing ink raw materials: the double-active-group printing ink raw materials comprise 5-30% of dye, 2-30% of humectant, 10-20% of cosolvent, 0.1-0.2% of PH regulator and bactericide, and the balance of deionized water, and then the printing ink is prepared by mixing the paste, the humectant, the cosolvent, the PH regulator, the bactericide and the balance of deionized water, the paste comprises 0.5-1% of sodium alginate, 0-0.3% of baking soda, 0-3% of sodium acetate, 0-3% of sodium propionate, 1-2% of reserve salt and 0-1.5% of penetrant, the invention relates to the technical field of digital printing, the printing color domain space is increased on the premise of ensuring the color fastness, so that the color is fuller, and the layers are richer; urea is not used in fabric pretreatment, meanwhile, due to the fact that the reaction performance is improved by about 20% or above, unreacted dye falling off in water washing is correspondingly reduced, the content of ammonia nitrogen, pigment, COD and BOD5 in sewage is improved, and the method is more environmentally friendly.

Description

Technical Field

[0001] The present invention relates to the technical field of digital printing, and specifically to the application of digital printing ink based on reactive dyes with medium to high reactive groups. Background Art

[0002] Traditional reactive printing usually prepares printing color paste by the full formula method, which generally includes: thickener, dye, alkali agent, urea, antioxidant, water, etc.

[0003] Traditional printing process: Prepare the above-mentioned printing color paste, and then transfer the printing color paste to the fabric through different printing methods, such as rotary screen, flat screen, etc., and then go through drying - fixation (steaming) - washing to complete the printing process.

[0004] In this process, in order to improve the reaction degree between the dye and the fiber during the fixation step, more steam condensate needs to be provided between the fiber and the dye to increase the penetration of the dye into the fabric and increase the reaction ratio between the dye and the fiber. Therefore, urea is added as a moisture absorbent in the color paste, and at the same time, an alkali agent necessary for the reaction between the reactive dye and the fiber must be contained.

[0005] In the color paste prepared by the full formula method, due to the presence of an alkali agent, when the pH value reaches above 10, the reactive dye in the color paste will undergo hydrolysis reaction with water (the hydrolyzed dye can no longer react with the fiber), resulting in a decrease in the strength of the dye as the hydrolysis reaction proceeds, which is not conducive to maintaining color stability. This hydrolysis reaction increases with the reactivity of the dye (increase in the number of reactive groups), so traditional reactive printing has to choose reactive dyes with low reactivity.

[0006] Hydrolysis reaction of reactive dyes:

[0007] Dye-Clx + H2O → Dye-OH + HCl

[0008] Dye-SO2-CH=CH2 + H2O → Dye-SO2-CH2CH2OH

[0009] Dye-Clx represents monochloro-s-triazine reactive dye, and Dye-OH is the hydrolyzed product.

[0010] Dye-SO2-CH=CH2 represents vinyl sulfone group reactive dye.

[0011] Reactive dyes can be roughly divided into single-reactive group, double-reactive group and multi-reactive group according to the number of reactive groups. At present, the dye inks used in digital printing continue the inertia of traditional printing and still use single-reactive group dyes with low reactivity. Except for black ink, because the color of monochlorotriazine dye cannot reach the visual effect of black, and at the same time, the alkalinity required for the reaction of black with other dyes needs to be considered, so reactive black with a slightly higher reactivity of vinyl sulfone group is used. However, in the process of digital printing, the dye ink is a separate system, and auxiliaries such as urea and alkali agent are on the pre-treated fabric, so there is no hydrolysis problem of the dye ink like traditional printing color paste.

[0012] In order to obtain deeper and more vivid colors in existing digital printing, usually a finishing solution containing 6-15% urea is padded on the fabric during pre-treatment to promote more condensed moisture to be generated on the fabric surface during the steaming and fixing process to improve the reaction performance between the dye and the fabric fiber. At the same time, in order to ensure the pH value necessary for the reaction between the dye and the fiber, a relatively strong alkali agent is also used, so that the pH value of the fabric surface reaches between 10 and 12. The result is that while the dye reacts with the fabric, the hydrolysis reaction of the dye also occurs simultaneously. Therefore, the average fixation rate of single-reactive group dyes is about 66%. For digital printing fabrics with medium and high reactivity reactive dyes, urea is not required for pre-treatment, less condensed moisture is generated during fixation, and the pH value of the fabric surface is controlled below pH 10 required for hydrolysis reaction. Therefore, while ensuring the reaction between the dye and the fabric, the occurrence of hydrolyzed dyes is reduced, and the average fixation rate of medium and high reactivity reactive dyes can reach 86%. Therefore, to obtain the same depth of color, more dyes need to be added for single-reactive group dyes to participate in the reaction. At the same time, due to the use of urea, during the washing process after the fixation of the printed fabric, a large amount of unreacted and hydrolyzed dyes and urea need to be washed off, resulting in high contents of ammonia nitrogen, pigments, COD and BOD5 in the sewage, which is not environmentally friendly. Summary of the Invention

[0013] Aiming at the deficiencies of the prior art, the present invention provides the application of digital printing ink based on medium and high reactivity group reactive dyes, which solves the problems of high dye consumption and high contents of ammonia nitrogen, pigments, COD and BOD5 in the sewage during the existing printing process, which is not environmentally friendly.

[0014] To achieve the above objectives, the present invention is realized through the following technical solutions: the application of digital printing ink based on medium and high reactivity group reactive dyes, including thickener and raw materials for double-reactive group printing ink:

[0015] The raw materials for the double-reactive group printing ink include: 5-30% dye, 2-30% humectant, 10-20% cosolvent, pH regulator, 0.1-0.2% bactericide, and deionized water is added to make up to 100%, and then mixed to make printing ink;

[0016] The paste includes: 0.5 - 1% sodium alginate, 0 - 3% sodium bicarbonate, 0 - 3% sodium acetate, 0 - 3% sodium propionate, 1 - 2% anti - staining salt, 0 - 1.5% penetrant.

[0017] Preferably, the moisturizer is pyrrolidone and glycol, the co - solvent is ethylene glycol and ethylene glycol ether, the pH regulator is acetic acid, the pH is adjusted to 5 - 8, and the bactericide is difenoconazole and isothiazolinone.

[0018] Preferably, the application of the printing ink includes:

[0019] S1: First, pre - treat the fabric. After pre - treatment, use a digital printing machine to directly spray the printing ink onto the fabric to obtain a precisely printed pattern.

[0020] S2: Then dry the printed fabric to obtain a dry printed fabric, and then steam and fix the dry printed fabric to obtain a semi - finished printed fabric.

[0021] S3: Finally, wash the semi - finished printed fabric to remove the paste, unfixed dyes and auxiliary impurities to obtain a clean and finished final printed fabric.

[0022] Preferably, the pre - treatment is: dissolve the paste and auxiliary agents in water to obtain a finishing solution, then pass the fabric through the finishing solution, roll - press the soaked fabric to squeeze out the excess finishing solution in the fabric, and then dry it to obtain a dry pre - treated fabric.

[0023] Beneficial effects

[0024] The present invention provides the application of digital printing ink based on medium - to - high - reactivity group reactive dyes, having the following beneficial effects: increasing the printing color gamut space while ensuring color fastness, making the colors more saturated and the layers more abundant; not using urea in the fabric pre - treatment, and at the same time, because the reaction performance is improved by more than about 20%, the unfixed dyes falling off during washing are correspondingly reduced, improving the contents of ammonia nitrogen, pigment, COD and BOD5 in the sewage, and being more environmentally friendly; reducing the amount of dye used, with better economy. Description of the drawings

[0025] Figure 1 It is a schematic diagram of the ink composition of the active digital printing of the present invention.

[0026] Figure 2 It is a conventional ink composition. Specific embodiments

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0028] Please refer to Figure 1-2 , the present invention provides a technical solution: an application based on a digital printing ink of a medium-high reactive group reactive dye, including a thickener and a raw material for a double-reactive group printing ink:

[0029] The raw material for the double-reactive group printing ink includes: 5-30% of a dye, 2-30% of a humectant, 10-20% of a co-solvent, a pH regulator, 0.1-0.2% of a bactericide, and deionized water to make up to 100%, and then they are mixed to make a printing ink;

[0030] The thickener includes: 0.5-1% of sodium alginate, 0-3.% of sodium bicarbonate, 0-3% of sodium acetate, 0-3% of sodium propionate, 1-2% of anti-staining salt, and 0-1.5% of penetrant.

[0031] Further, the humectant is pyrrolidone and glycol, the co-solvent is ethylene glycol and ethylene glycol ether, the pH regulator is acetic acid, the pH is adjusted to 5-8, and the bactericide is difenoconazole and isothiazolinone.

[0032] Further, the application of the printing ink includes:

[0033] S1: First, pre-treat the fabric. After pre-treatment, use a digital printing machine to directly spray the printing ink onto the fabric to obtain a precisely printed pattern;

[0034] S2: Then dry the printed fabric to obtain a dry printed fabric, and then steam and fix the dry printed fabric to obtain a semi-finished printed fabric;

[0035] S3: Finally, wash the semi-finished printed fabric to remove the thickener, unfixed dyes and auxiliary impurities to obtain a clean and complete final printed fabric.

[0036] The digital printing machine is an existing conventional device. It is a printing method based on digital image technology and computer control. It converts the designed pattern into a digital signal and uses the printing device to directly spray the ink or dye onto the fabric to achieve precise printing of the pattern. Its usage method and operation steps belong to existing technical knowledge, so there is no need to introduce its usage process in detail.

[0037] Process of digital printing: Pretreat the fabric to be printed -- Digital printing -- Drying -- Fixing (steaming) -- Washing.

[0038] In printing with dual reactive dyes, under the condition of using an appropriate alkali agent, the color yield can be higher than that of the traditional combination of baking soda and urea.

[0039] Furthermore, the pretreatment is as follows: Dissolve the paste and additives in water to obtain a finishing solution, then pass the fabric through the finishing solution, perform a rolling treatment on the soaked fabric, squeeze out the excess finishing solution in the fabric, and then perform drying to obtain a dry pretreated fabric.

[0040] Those skilled in the art should process the fabric parts in this case in sequence. For the specific processing and operation sequence, reference should be made to the following working principle. The detailed connection means are well-known techniques in this field. The following mainly introduces the working principle and process.

[0041] Example: First, pretreat the fabric. After pretreatment, use a digital printer to directly spray the printing ink onto the fabric to obtain a precisely printed pattern; then perform a drying treatment on the printed fabric to obtain a dry printed fabric, and then perform steaming and fixing on the dry printed fabric to obtain a semi-finished printed fabric; finally, wash the semi-finished printed fabric to remove the paste, unfixed dyes, and additive impurities to obtain a clean and complete final printed fabric.

[0042] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation. An element defined by the statement "comprising an..." does not exclude the existence of additional identical elements in the process, method, article or device comprising the element.

[0043] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Application of digital printing ink based on reactive dyes with medium and high reactive groups, characterized in that: Including paste and dual-active base printing ink raw materials: The raw materials of the dual-active group printing ink include: 5-30% dye, 2-30% moisturizer, 10-20% cosolvent, PH regulator, 0.1-0.2% bactericide and deionized water to make up to 100%, and then mixed to make the printing ink; The paste comprises: 0.5-1% sodium alginate, 0-3.% baking soda, 0-3% sodium acetate, 0-3% sodium propionate, 1-2% resist salt and 0-1.5% penetrant.

2. The use of digital printing ink based on medium and high reactive groups of reactive dyes according to claim 1, characterized in that: The moisturizing agent is pyrrolidone and ethylene glycol, the cosolvent is ethylene glycol and ethylene glycol ether, the pH regulator is acetic acid, and the pH is adjusted to 5-8, and the bactericide is difenoconazole and isothiazolinone.

3. The use of digital printing ink based on reactive dyes with medium and high reactive groups according to claim 1, characterized in that: Applications of printing inks include: S1: First, the fabric is pretreated, and then the printing ink is directly sprayed onto the fabric using a digital printing machine to obtain a precise printed pattern; S2: drying the printed fabric to obtain a dried printed fabric, and then steaming and fixing the dried printed fabric to obtain a semi-finished printed fabric; S3: Finally, the semi-finished printed fabric is washed to remove the paste, unfixed dye and auxiliary impurities to obtain a clean and finished final printed fabric.

4. The use of digital printing ink based on medium and high reactive groups reactive dyes according to claim 3, characterized in that: The pretreatment is as follows: dissolving the paste and the auxiliary agent in water to obtain a finishing liquid, then passing the fabric through the finishing liquid, performing a pressing treatment on the soaked fabric, pressing out the excess finishing liquid in the fabric, and then drying to obtain a dry pretreated fabric.

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