Easy-to-remove printing paste constructed based on serous membrane strong-hydrophilicity microphase accumulation area as well as preparation method and application of easy-to-remove printing paste

Abstract

The invention relates to the technical field of easy-to-remove printing paste, and discloses an easy-to-remove printing paste constructed on the basis of a serous membrane strong hydrophilic microphase accumulation region, and a preparation method and application of the easy-to-remove printing paste. The preparation method comprises the following steps: preparing raw materials (double-bond silicon spheres, acrylic acid, a silane coupling agent, an initiator, a composite solvent, sodium carboxymethyl starch or sodium carboxymethyl cellulose, water, inorganic alkali and a viscosity modifier); a step of graft polymerization; a post-treatment step; and preparing original printing paste, so as to prepare the printing paste easy to remove. The printing paste easy to remove can be used for preparing reactive dye printing paste so as to construct a strong hydrophilic microphase accumulation area easier to elute in a printing paste film, and the elution property of the printing paste can be remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of easy-to-remove printing paste technology, specifically to an easy-to-remove printing paste based on a microphase aggregation region with strong hydrophilicity in the paste film, its preparation method, and its application. Background Technology

[0002] Sodium alginate has long been considered an ideal paste for reactive dye printing due to its excellent water-holding, water-retention, rheological, and chemical compatibility. However, its high price and unstable supply make it difficult to meet the needs of the printing and dyeing industry's industrial development. While sodium carboxymethyl starch (CMS-Na) and sodium carboxymethyl cellulose (CMC-Na) are potential alternatives to sodium alginate, their readily available and inexpensive raw materials, coupled with the difficulty in producing highly substituted products, lead to problems such as low printing desizing efficiency, poor hand feel of printed fabrics, and poor color fastness.

[0003] Currently, the main solutions to these problems are:

[0004] ① Combining CMC-Na or CMS-Na with sodium alginate can lead to a negative problem of decreased stability in the performance of the composite paste, which brings uncertainty to its large-scale application.

[0005] ② Developing highly substituted CMC-Na and CMS-Na, but their production is difficult, inevitably leading to a series of application problems due to high costs;

[0006] ③ Upgrading cleaning equipment, strengthening desizing processes, optimizing cleaning auxiliaries, and innovating printing technologies, but this will undoubtedly lead to problems such as lengthy production processes, complex process formulas, increased production costs, and increased water and electricity consumption.

[0007] Currently, the main technologies for preparing and applying printing pastes that aim to improve the desizing rate or reduce the amount of paste used (reduce the burden of desizing) include the following:

[0008] 1. A technical solution for compounding sodium carboxymethyl starch and sodium carboxymethyl cellulose in a certain proportion.

[0009] For example, the paper "CMS / CMC Compound and Its Application in Reactive Printing" by Xu Fuli, Zhou Peiwen, Cao Changqing, et al. (Issue 12, 2024) discloses the preparation of cold water soluble sodium carboxymethyl cellulose and sodium carboxymethyl starch using bagasse cellulose and ordinary corn starch. The paper explores the effects of different compounding ratios on rheology, water retention, storage stability, chemical compatibility and printing effect, and compares the printing effect with that of sodium alginate.

[0010] The composite paste exhibits significantly improved shear resistance, water retention, and storage stability, along with good chemical compatibility. However, its screen penetration and permeability are low, and the covalent bonding between residual hydroxyl groups and dyes is not effectively suppressed. This compounding scheme merely alleviates problems such as excessive staining, difficulty in desizing, low fastness, and poor hand feel by diluting the proportion of sodium carboxymethyl starch or sodium carboxymethyl cellulose in the composite, without addressing the fundamental issues.

[0011] 2. Technical solutions for improving the degree of substitution of sodium carboxymethyl starch and sodium carboxymethyl cellulose.

[0012] For example, the paper "Physicochemical Properties of Highly Substituted Carboxymethyl Starch" by Zhang Benshan, Guo Chenfeng, Li Weimin, et al. (Journal of South China University of Technology (Natural Science Edition), No. 3, 2017) discloses the preparation of highly substituted carboxymethyl starch in the alcohol phase using native corn starch as raw material, and the determination and analysis of its physicochemical properties, which are compared with those of native corn starch.

[0013] For example, the paper "Study on Microwave Synthesis of Carboxymethyl Starch" by Li Wei, Xin Wenfang, and An Guorong (Modern Agricultural Science and Technology, No. 11, 2016) discloses the preparation of sodium carboxymethyl starch from corn starch using a microwave reaction. The results show that the DS value is maximized when the corn starch is microwave modified for 3.0 min, the starch to chloroacetic acid ratio is 1.0:2.5, and the sodium hydroxide dosage is 3.0 g.

[0014] Highly substituted carboxymethyl starch exhibits significantly better transparency and freeze-thaw stability than native corn starch, and its washability is also considerably better. However, incompletely washed-out sodium carboxymethyl starch tends to form a hard film on fabric surfaces, reducing fabric softness and drape. Furthermore, this technological solution is technically challenging and costly to produce, making widespread application difficult.

[0015] 3. Innovative printing technology, enhanced degreasing process, and optimized process equipment technical solutions.

[0016] For example, the paper "Research on the Application of Foam Technology in Reactive Dye Printing" by Di Jiale, Meng Yuan, Qian Di, et al. (Shandong Chemical Industry, Vol. 50, No. 17, 2021) discloses the use of a foam system of reactive dyes to print on cotton fabrics. The paper explores the foaming performance of the foaming liquid, the ratio of sodium carboxymethyl starch to sodium carboxymethyl cellulose in the paste, studies the printing performance of the foam color paste, and evaluates the effect of foam printing.

[0017] Foam technology for reactive dye printing can significantly reduce the amount of paste used (by 45% to 55%) and the amount of liquid carried, resulting in lower requirements for desizing of printed fabrics and a significantly lighter burden of desizing. However, this technology is not only limited by the printing effect, but also has significantly higher requirements for production hardware and production technology. Summary of the Invention

[0018] The technical problem to be solved by this invention is to provide an easy-to-remove printing paste based on a strongly hydrophilic microphase aggregation region constructed in the printing paste film, its preparation method, and its application. The easy-to-remove printing paste prepared using this method can be used in the formulation of reactive dye printing pastes to construct a more easily washable strongly hydrophilic microphase aggregation region in the printing paste film, significantly improving the washability of the printing paste. In this invention, polyacrylic acid polymers with a significantly cross-linked structure are fixed on the surface of micron-sized silica microspheres. This not only ensures the relative concentration of the strongly hydrophilic microphase region, but also the numerous long chains of strongly hydrophilic ions on the surface of the micron-sized silica microspheres enhance the thickening ability of the printing paste without harming its rheological properties. This printing paste film with a physically "defective" structure provides a "breakthrough" for water to rapidly wet, penetrate, and wash away the printing paste film during its soaping process, effectively enhancing the washing efficiency of the printing paste.

[0019] To achieve the above objectives, the present invention provides a method for preparing an easy-to-de-spread printing paste based on a microphase aggregation region with strong hydrophilicity in the paste film, comprising the following steps:

[0020] (1) Raw material preparation: double bond silica balls, acrylic acid, silane coupling agent, initiator, composite solvent, sodium carboxymethyl starch or sodium carboxymethyl cellulose, water, inorganic alkali and viscosity modifier;

[0021] The double bond content of the double bond silicon spheres is 0.2-1%, the particle size is 2-9 μm, and the particle size polydispersity index is 0.15-0.25;

[0022] The silane coupling agent includes one of vinyltrimethoxysilane, methacryloyloxymethyltrimethoxysilane, 3-acryloyloxypropylmethyldimethoxysilane, and 3-methacryloyloxypropyltrimethoxysilane.

[0023] The composite solvent is a mixed solution of deionized water and ethanol, and the mass fraction of ethanol in the composite solvent is 20-40%.

[0024] The mass ratio of the double-bonded silicon spheres, acrylic acid, and silane coupling agent is 1:(2-5):(0.1-0.3), and the mass of the initiator is 1.5-3.5% of the total mass of the double-bonded silicon spheres, acrylic acid, and silane coupling agent.

[0025] The mass ratio of sodium carboxymethyl starch or sodium carboxymethyl cellulose to the double-bonded silicon spheres is 50-150:1.

[0026] (2) Graft polymerization step: The double bonded silica spheres are reacted with acrylic acid, silane coupling agent and initiator in the composite solvent to obtain a hydrophilic modified silica microsphere dispersion;

[0027] (3) Post-processing steps: The hydrophilic modified silica microsphere dispersion is filtered, dried and ground to obtain hydrophilic modified silica microsphere powder;

[0028] (4) Steps for preparing printing paste: The hydrophilic modified silica microsphere powder is mixed with sodium carboxymethyl starch or sodium carboxymethyl cellulose, water and inorganic alkali to prepare an easy-to-remove printing paste.

[0029] Preferably, the mass of the composite solvent is 8 to 12 times the total mass of the double-bonded silicon spheres, acrylic acid, and silane coupling agent.

[0030] Preferably, the mass of the water is 8 to 12 times the mass of the sodium carboxymethyl starch or sodium carboxymethyl cellulose.

[0031] Preferably, the initiator includes one of ammonium persulfate and potassium persulfate.

[0032] Preferably, the water is soft water with a total hardness not exceeding 50 ppm CaCO3.

[0033] Preferably, the viscosity modifier is soft water with a total hardness not exceeding 50 ppm CaCO3.

[0034] Preferably, the inorganic base includes one or two of sodium hydroxide, sodium carbonate, and sodium bicarbonate.

[0035] Preferably, the pH value of the easy-to-de-seal printing paste constructed based on the strongly hydrophilic microphase aggregation region of the paste film is 9-11.

[0036] Preferably, the viscosity of the easy-to-de-spread printing paste constructed based on the strongly hydrophilic microphase aggregation region of the paste film is 15000-25000 mPa·s.

[0037] Preferably, the specific process of step (2) includes:

[0038] (2.1) Add 60-80% of the total mass of the composite solvent, double bond silicon spheres, 30-60% of the total mass of acrylic acid, and 30-60% of the total mass of silane coupling agent into the reactor, mix, and control the system temperature at 70-80℃;

[0039] (2.2) Mix the initiator, the remaining acrylic acid, the remaining coupling agent and the remaining composite solvent, and then, under stirring, at 70-80°C, uniformly drop the resulting mixture into the reactor over 60-90 minutes.

[0040] (2.3) Under stirring, the material in the reactor is kept at 75-85℃ for 30-60 min to obtain a hydrophilic modified silica microsphere dispersion.

[0041] Preferably, the specific process of step (3) includes:

[0042] The hydrophilic modified silica microsphere dispersion was filtered, and the resulting filter cake was vacuum dried. The dried filter cake was then ground to obtain hydrophilic modified silica microsphere powder.

[0043] Preferably, the specific process of step (4) includes:

[0044] The hydrophilic modified silica microsphere powder, sodium carboxymethyl starch or sodium carboxymethyl cellulose, and water are mixed, and then an inorganic alkali is added to control the pH value of the system. After stirring and gelatinizing, a viscosity regulator is added to adjust the viscosity of the system to obtain an easy-to-remove printing paste.

[0045] A second aspect of the present invention provides an easy-to-de-seal printing paste prepared by the above method, based on the construction of a microphase aggregation region with strong hydrophilicity in the film.

[0046] The third aspect of this invention proposes the application of the above-mentioned easy-to-remove printing paste based on the strongly hydrophilic microphase aggregation region of the paste film in fabric printing.

[0047] Compared with the prior art, the method of the present invention has the following advantages and features:

[0048] 1. In this invention, by constructing a microphase aggregation region with stronger hydrophilicity in the carboxymethyl starch printing paste / film, a "breakthrough" is provided for water to quickly wet, penetrate and wash away the printing paste during the soaping process after printing, thereby forming and gradually expanding the water diffusion channel, effectively enhancing the washing efficiency of the printing soaping on the paste.

[0049] 2. In this invention, in order to ensure that the sodium polyacrylate polymer with stronger hydrophilicity and easier wash-out is relatively concentratedly dispersed in the printing paste / film, a microphase aggregation region with stronger hydrophilicity and easier wash-out (i.e., the heterogeneous aggregation structure of the printing paste) is constructed in the printing paste / film, and the sodium polyacrylate polymer chain is fixed on the surface of solid micron-sized silica microspheres.

[0050] 3. In this invention, to solve the problem of difficulty in hydrophilic grafting reaction of double-bonded silicon spheres caused by heterogeneous reaction between solid and liquid, the polarity (alcohol-to-water ratio) of the reaction medium is adjusted so that the silane coupling agent can be effectively adsorbed on the surface of the double-bonded silicon spheres. Under the action of the initiator, the polymerization of the double-bonded silicon spheres and acrylic acid is completed simultaneously on the surface of the double-bonded silicon spheres, realizing the hydrophilic grafting reaction of double-bonded silicon spheres with acrylic acid as the "bridge".

[0051] 4. In this invention, the polyacrylic acid "crosslinking" structure with silica microspheres as the crosslinking center has good rheological and thickening properties. Therefore, its use in modified starch will not deteriorate the paste formation rate and rheological properties of the composite paste, and may even optimize the application performance of the composite paste to a certain extent. Detailed Implementation

[0052] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0053] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0054] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating relative importance or implying the number of technical features indicated. Therefore, unless otherwise stated, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; "multiple" means two or more. The term "comprising" and any variations thereof mean non-exclusive inclusion, where one or more other features, integers, steps, operations, units, components, and / or combinations thereof may be present or added.

[0055] In a first aspect, the present invention proposes a method for preparing an easy-to-de-spread printing paste based on a microphase aggregation region with strong hydrophilicity in the paste film, comprising the following steps:

[0056] (1) Raw material preparation: double bond silica spheres (the “double bond silica spheres” mentioned in this invention refer to double bond mesoporous silica spheres prepared by using monomers containing double bonds during the growth of mesoporous silica sphere molecular chains, and the double bond content of silica spheres can be adjusted by adjusting the amount of the monomers containing double bonds), acrylic acid, silane coupling agent, initiator, composite solvent, sodium carboxymethyl starch or sodium carboxymethyl cellulose, water, inorganic alkali and viscosity modifier;

[0057] The double bond content (in this invention, "double bond content" refers to the percentage of the mass of -CH=CH2 in the preparation formula of double bond mesoporous silica spheres to the total mass of monomers) of the double bond silica spheres is 0.2-1 wt.%, the particle size is 2-9 μm, and the particle size polydispersity index is 0.15-0.25.

[0058] The silane coupling agent includes one of vinyltrimethoxysilane, methacryloyloxymethyltrimethoxysilane, 3-acryloyloxypropylmethyldimethoxysilane, and 3-methacryloyloxypropyltrimethoxysilane.

[0059] The composite solvent is a mixed solution of deionized water and ethanol, and the mass fraction of ethanol in the composite solvent is 20-40%.

[0060] The mass ratio of the double-bonded silicon spheres, acrylic acid, and silane coupling agent is 1:(2-5):(0.1-0.3);

[0061] The mass of the initiator is 1.5 to 3.5% of the total mass of the double-bonded silica spheres, acrylic acid, and silane coupling agent;

[0062] The mass ratio of sodium carboxymethyl starch or sodium carboxymethyl cellulose to the double-bonded silicon spheres is 50-150:1.

[0063] (2) Graft polymerization step: The double bonded silica spheres are reacted with acrylic acid, silane coupling agent and initiator in the composite solvent to obtain a hydrophilic modified silica microsphere dispersion;

[0064] (3) Post-processing steps: The hydrophilic modified silica microsphere dispersion is filtered, dried and ground to obtain hydrophilic modified silica microsphere powder;

[0065] (4) Steps for preparing printing paste: The hydrophilic modified silica microsphere powder is mixed with sodium carboxymethyl starch or sodium carboxymethyl cellulose, water and inorganic alkali to prepare an easy-to-remove printing paste.

[0066] Compared with the prior art, the method of the present invention has the following advantages and features:

[0067] 1. In this invention, by constructing a more hydrophilic microphase aggregation region in sodium carboxymethyl starch or sodium carboxymethyl cellulose printing paste / film, a "breakthrough" is provided for water to rapidly wet, penetrate and wash away the printing paste during the soaping process after printing, thereby forming and gradually expanding the water diffusion channel, effectively enhancing the washing efficiency of the printing paste by soaping.

[0068] 2. In this invention, in order to ensure that the sodium polyacrylate polymer with stronger hydrophilicity and easier wash-out is relatively concentratedly dispersed in the printing paste / film, a microphase aggregation region with stronger hydrophilicity and easier wash-out (i.e., the heterogeneous aggregation structure of the printing paste) is constructed in the printing paste / film, and the sodium polyacrylate polymer chain is fixed on the surface of solid micron-sized silica microspheres.

[0069] 3. In this invention, to solve the problem of difficulty in hydrophilic grafting reaction of double-bonded silicon spheres caused by heterogeneous reaction between solid and liquid, the polarity (alcohol-to-water ratio) of the reaction medium is adjusted so that the silane coupling agent can be effectively adsorbed on the surface of the double-bonded silicon spheres. Under the action of the initiator, the polymerization of the double-bonded silicon spheres and acrylic acid is completed simultaneously on the surface of the double-bonded silicon spheres, realizing the hydrophilic grafting reaction of double-bonded silicon spheres with acrylic acid as the "bridge".

[0070] 4. In this invention, the polyacrylic acid "crosslinking" structure with silica microspheres as the crosslinking center has good rheological and thickening properties. Therefore, its use in modified starch will not deteriorate the paste formation rate and rheological properties of the composite paste, and may even optimize the application performance of the composite paste to a certain extent.

[0071] In a preferred embodiment, the content of double bonds in the double-bonded silicon spheres can be 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, or 1 wt.%, more preferably 0.2 to 0.4 wt.%.

[0072] In a preferred embodiment, the ethanol has a mass fraction of 25% to 35% in the composite solvent. Specifically, the mass fraction of ethanol in the composite solvent can be 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35%.

[0073] In a preferred embodiment, the mass ratio of the double-bonded silicon spheres, acrylic acid, and silane coupling agent can be 1:2:0.1, 1:3:0.1, 1:4:0.1, 1:5:0.1, 1:2:0.2, 1:3:0.2, 1:4:0.2, 1:5:0.2, 1:2:0.3, 1:3:0.3, 1:4:0.3, or 1:5:0.3.

[0074] In a preferred embodiment, the mass of the initiator can be 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3%, 3.1%, 3.2%, 3.3%, 3.4%, or 3.5% of the total mass of the double-bonded silica balls, acrylic acid, and silane coupling agent.

[0075] In a preferred embodiment, the mass ratio of sodium carboxymethyl starch or sodium carboxymethyl cellulose to the double-bonded silicon spheres can be 50:1, 60:1, 70:1, 80:1, 90:1, 100:1, 110:1, 120:1, 130:1, 140:1, or 150:1.

[0076] In a preferred embodiment, the mass of the initiator is 1.6% to 2% of the total mass of the double-bonded silica spheres, acrylic acid, and silane coupling agent. Specifically, the mass of the initiator can be 1.6%, 1.7%, 1.8%, 1.9%, or 2% of the total mass of the double-bonded silica spheres, acrylic acid, and silane coupling agent.

[0077] In a preferred embodiment, the mass ratio of sodium carboxymethyl starch or sodium carboxymethyl cellulose to the double-bonded silicon spheres is 80–100:1. Specifically, the mass ratio of sodium carboxymethyl starch or sodium carboxymethyl cellulose to the double-bonded silicon spheres can be 80:1, 81:1, 82:1, 83:1, 84:1, 85:1, 86:1, 87:1, 88:1, 89:1, 90:1, 91:1, 92:1, 93:1, 94:1, 95:1, 96:1, 97:1, 98:1, 99:1, or 100:1.

[0078] In a preferred embodiment, the mass of the composite solvent is 8 to 12 times the total mass of the double-bonded silicon spheres, acrylic acid, and silane coupling agent. Specifically, the mass of the composite solvent can be 8, 9, 10, 11, or 12 times the total mass of the double-bonded silicon spheres, acrylic acid, and silane coupling agent.

[0079] In a preferred embodiment, the mass of the water is 8 to 12 times the mass of the sodium carboxymethyl starch or sodium carboxymethyl cellulose. Specifically, the mass of the water can be 8, 9, 10, 11, or 12 times the mass of the sodium carboxymethyl starch or sodium carboxymethyl cellulose. In a preferred case, the mass of the water is 10 to 12 times the mass of the sodium carboxymethyl starch or sodium carboxymethyl cellulose.

[0080] In a preferred embodiment, the initiator comprises one of ammonium persulfate and potassium persulfate, for example, ammonium persulfate or persulfate. Preferably, the initiator is ammonium persulfate or potassium persulfate.

[0081] In a preferred embodiment, the water is soft water with a total hardness not exceeding 50 ppm CaCO3.

[0082] In a preferred embodiment, the viscosity modifier is soft water with a total hardness not exceeding 50 ppm CaCO3.

[0083] In a preferred embodiment, the inorganic base includes one or two of sodium hydroxide, sodium carbonate, and sodium bicarbonate. For example, it can be sodium hydroxide, sodium carbonate, or sodium bicarbonate, or it can be a mixture of sodium hydroxide and sodium carbonate, a mixture of sodium hydroxide and sodium bicarbonate, or a mixture of sodium carbonate and sodium bicarbonate.

[0084] In a preferred embodiment, the pH value of the easily desizing printing paste constructed based on the strongly hydrophilic microphase aggregation region of the film is 9-11, preferably 9.5-10.5. In this invention, the amount of inorganic alkali used is the amount required to adjust the pH value of the reaction system to 9-11.

[0085] In a preferred embodiment, the viscosity of the easily detachable printing paste constructed based on the strongly hydrophilic microphase aggregation region of the film is 15,000–25,000 mPa·s, preferably 15,000–18,000 mPa·s. In this invention, the amount of the viscosity modifier used is the amount required to adjust the viscosity of the system to 15,000–25,000 mPa·s.

[0086] In a preferred embodiment, step (2) specifically includes:

[0087] (2.1) Add 60-80% of the total mass of the composite solvent, double bond silicon spheres, 30-60% of the total mass of acrylic acid, and 30-60% of the total mass of silane coupling agent into the reactor, mix, and control the system temperature at 70-80℃;

[0088] (2.2) Mix the initiator, the remaining acrylic acid, the remaining coupling agent and the remaining composite solvent, and then, under stirring, at 70-80°C, uniformly drop the resulting mixture into the reactor over 60-90 minutes.

[0089] (2.3) Under stirring, the material in the reactor is kept at 75-85℃ for 30-60 min to obtain a hydrophilic modified silica microsphere dispersion.

[0090] In this invention, by adopting a step-by-step feeding design of "base addition + drop addition", the copolymerization reaction between acrylic acid, coupling agent and double bond silicon spheres is more effective, and the self-polymerization reaction of acrylic acid and coupling agent, which are not beneficial to modification, as well as the copolymerization reaction between the two, are effectively suppressed.

[0091] In a preferred embodiment, step (3) includes the following specific process:

[0092] The hydrophilic modified silica microsphere dispersion was filtered, and the resulting filter cake was vacuum dried. The dried filter cake was then ground to obtain hydrophilic modified silica microsphere powder.

[0093] In a preferred embodiment, step (4) specifically includes the following process:

[0094] The hydrophilic modified silica microsphere powder, sodium carboxymethyl starch or sodium carboxymethyl cellulose, and water are mixed. Then, an inorganic alkali is added to control the pH value of the system. After thorough stirring and gelatinization, a viscosity regulator is added to adjust the viscosity of the system to obtain an easy-to-remove printing paste.

[0095] In the method of the present invention, an inorganic alkali is added to control the pH value of the system to 9-11, and a viscosity regulator is added to adjust the viscosity of the system to 15000-25000 mPa·s.

[0096] Secondly, the present invention proposes an easy-to-de-spread printing paste prepared by the above method, based on the construction of a microphase aggregation region with strong hydrophilicity in the film.

[0097] The easy-to-remove printing paste prepared by the method provided in this invention can be used for the preparation of reactive dye printing pastes. It constructs a strongly hydrophilic microphase aggregation region in the printing paste film that is easier to wash out, significantly improving the washability of the printing paste. In this invention, the easy-to-remove printing paste not only ensures the relatively concentrated strong hydrophilic microphase region, but its cross-linking structure also enhances the thickening ability of the printing paste and is harmless to the rheological properties of the paste. This printing paste film with a physically "defective" structure provides a "breakthrough" for water to rapidly wet, penetrate, and wash out the printing paste film during its soaping process, effectively enhancing the washing efficiency of the printing paste. The finished easy-to-remove printing paste prepared by the method provided in this invention must be stored in a cool, dry place in a sealed container.

[0098] Thirdly, this invention proposes an application of the easily detachable printing paste constructed based on the strongly hydrophilic microphase aggregation region of the paste film in fabric printing. The easily detachable printing paste provided by this invention, constructed based on the strongly hydrophilic microphase aggregation region of the paste film, can be widely used in printing on various fabrics, specifically in the preparation of reactive dye printing pastes, and can significantly improve the washout properties of the printing paste.

[0099] The following examples further illustrate the easy-to-de-dry printing paste based on the strongly hydrophilic microphase aggregation region of the paste film, its preparation method, and its application. These examples are implemented based on the technical solution of this invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of this invention is not limited to the following examples.

[0100] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following embodiments are commercially available.

[0101] Table 1

[0102]

[0103] In Table 1, the particle size of the double-bonded silica spheres is 2–9 μm, the polydispersity index is 0.15–0.25, and the water and viscosity modifier are both soft water with a total hardness not exceeding 50 ppm CaCO3.

[0104] Example 1: A method for preparing an easy-to-remove printing paste, the specific steps of which include:

[0105] (1) Raw material preparation, the specific selection and amount of the raw materials are shown in Table 1;

[0106] (2) Graft polymerization step, in which double bonded silica spheres are reacted with acrylic acid, silane coupling agent and initiator in a composite solvent to obtain a hydrophilic modified silica microsphere dispersion.

[0107] (2.1) Add 60% of the total mass of the composite solvent, double bond silica spheres, 40% of the total mass of acrylic acid, and 40% of the total mass of silane coupling agent to the reactor, mix thoroughly, and control the system temperature at 73°C.

[0108] (2.2) Dissolve the initiator, the remaining acrylic acid, and the remaining coupling agent in the remaining composite solvent, and uniformly drop them into the reactor over 60 min under stirring and at 73°C.

[0109] (2.3) The mixture was stirred and kept at 78°C for 50 min to obtain a hydrophilic modified silica microsphere dispersion.

[0110] (3) The post-processing step involves filtering, drying, and grinding the hydrophilic modified silica microsphere dispersion to obtain hydrophilic modified silica microsphere powder.

[0111] (3.1) The reaction system in step (2.3) is filtered and the filter cake is vacuum dried. The dried filter cake is then ground to obtain hydrophilic modified silica microsphere powder.

[0112] (4) The step of preparing printing paste involves mixing hydrophilic modified silica microsphere powder with sodium carboxymethyl starch or sodium carboxymethyl cellulose, water, and inorganic alkali to obtain an easy-to-remove printing paste.

[0113] (4.1) The hydrophilic modified silica microsphere powder obtained in step (3.1), sodium carboxymethyl starch or sodium carboxymethyl cellulose, and water are mixed. The pH of the reaction system is controlled to be 9.5 to 10.0 with an inorganic alkali. After the mixture is fully stirred and gelatinized, the viscosity of the system is adjusted to 16000±500 mPa·s with a viscosity regulator to obtain an easy-to-remove printing paste.

[0114] The easily detachable printing paste prepared in this embodiment can be used to formulate reactive dye printing pastes. It constructs a strongly hydrophilic microphase aggregation region in the printing paste film that is easier to wash out, significantly improving the washability of the printing paste. In this invention, the easily detachable printing paste not only ensures the relatively concentrated strong hydrophilic microphase region, but its cross-linking structure also enhances the thickening ability of the printing paste and is harmless to the rheological properties of the paste. This printing paste film with a physically "defective" structure provides a "breakthrough" for water to rapidly wet, penetrate, and wash out the printing paste film during its soaping process, effectively enhancing the washing efficiency of the printing paste.

[0115] The easy-to-remove printing paste (viscosity 16000±500mPa·s) prepared in this embodiment has a paste formation rate of 5.2%, that is, sodium carboxymethyl starch accounts for 5.2% of the total mass of the prepared easy-to-remove printing paste; at the process viscosity (5000~6000mPa·s), the rheological index PVI of the paste is 0.22; the desizing rate is 93%. Desizing process: After the white paste-printed fabric is dried, it is washed once with hot water at 60℃ for 5 minutes, and then rinsed twice with room temperature water for 5 minutes each time. The amount of water used each time is 20 times the dry weight of the white paste-printed fabric.

[0116] Storage of the product prepared in this embodiment: The finished product must be stored in a cool, dry place in a sealed container.

[0117] Example 2: A method for preparing an easy-to-remove printing paste, the specific steps of which include:

[0118] (1) Raw material preparation, the specific selection and amount of the raw materials are shown in Table 1;

[0119] (2) Graft polymerization step, in which double bonded silica spheres are reacted with acrylic acid, silane coupling agent and initiator in a composite solvent to obtain a hydrophilic modified silica microsphere dispersion.

[0120] (2.1) Add 68% of the total mass of the composite solvent, double bond silica spheres, 50% of the total mass of acrylic acid, and 50% of the total mass of silane coupling agent to the reactor, mix thoroughly, and control the system temperature at 75°C.

[0121] (2.2) Dissolve the initiator, the remaining acrylic acid, and the remaining coupling agent in the remaining composite solvent, and uniformly drop them into the reactor over 65 min under stirring and at 75°C.

[0122] (2.3) The mixture was stirred and kept at 80°C for 55 min to obtain a hydrophilic modified silica microsphere dispersion.

[0123] (3) The post-processing step involves filtering, drying, and grinding the hydrophilic modified silica microsphere dispersion to obtain hydrophilic modified silica microsphere powder.

[0124] (3.1) The reaction system in step (2.3) is filtered and the filter cake is vacuum dried. The dried filter cake is then ground to obtain hydrophilic modified silica microsphere powder.

[0125] (4) The step of preparing printing paste involves mixing hydrophilic modified silica microsphere powder with sodium carboxymethyl starch or sodium carboxymethyl cellulose, water, and inorganic alkali to obtain an easy-to-remove printing paste.

[0126] (4.1) The hydrophilic modified silica microsphere powder obtained in step (3.1), sodium carboxymethyl starch or sodium carboxymethyl cellulose, and water are mixed. The pH of the reaction system is controlled to be 10±0.5 with an inorganic alkali. After the mixture is fully stirred and gelatinized, the viscosity of the system is adjusted to 16000±500 mPa·s with a viscosity regulator to obtain an easy-to-remove printing paste.

[0127] The product prepared by the method of this invention can be used for the preparation of reactive dye printing pastes. It constructs a more easily elutable, strongly hydrophilic microphase aggregation region in the printing paste film, significantly improving the elutability of the printing paste. In this invention, the easily elutable printing paste not only ensures the relative concentration of the strongly hydrophilic microphase region, but its cross-linking structure also enhances the thickening ability of the printing paste without harming its rheological properties. This printing paste film with a physically "defective" structure provides a "breakthrough" for water to rapidly wet, penetrate, and elute the printing paste film during its soaping process, effectively enhancing the elution efficiency of the printing paste during soaping.

[0128] The easy-to-remove printing paste (viscosity 16000±500mPa·s) prepared in this embodiment has a paste formation rate of 5.3%, that is, sodium carboxymethyl starch accounts for 5.3% of the total mass of the prepared easy-to-remove printing paste; at the process viscosity (5000~6000mPa·s), the rheological index PVI of the paste is 0.21; the desizing rate is 95%. Desizing process: After the white paste-printed fabric is dried, it is washed once with hot water at 60℃ for 5 minutes, and then rinsed twice with room temperature water for 5 minutes each time. The amount of water used each time is 20 times the dry weight of the white paste-printed fabric.

[0129] Storage of products prepared by the method of this invention: The finished product must be sealed and stored in a cool, dry place.

[0130] Example 3: A method for preparing an easy-to-remove printing paste, the specific steps of which include:

[0131] (1) Raw material preparation, the specific selection and amount of the raw materials are shown in Table 1;

[0132] (2) Graft polymerization step, in which double bonded silica spheres are reacted with acrylic acid, silane coupling agent and initiator in a composite solvent to obtain a hydrophilic modified silica microsphere dispersion.

[0133] (2.1) Add 80% of the total mass of the composite solvent, double bonded silica spheres, 60% of the total mass of acrylic acid, and 60% of the total mass of silane coupling agent to the reactor, mix thoroughly, and control the system temperature at 80°C.

[0134] (2.2) Dissolve the initiator, the remaining acrylic acid, and the remaining coupling agent in the remaining composite solvent, and uniformly drop them into the reactor over 80 min under stirring and at 80°C.

[0135] (2.3) The mixture was stirred and kept at 85°C for 45 min to obtain a hydrophilic modified silica microsphere dispersion.

[0136] (3) The post-processing step involves filtering, drying, and grinding the hydrophilic modified silica microsphere dispersion to obtain hydrophilic modified silica microsphere powder.

[0137] (3.1) The reaction system in step (2.3) is filtered and the filter cake is vacuum dried. The dried filter cake is then ground to obtain hydrophilic modified silica microsphere powder.

[0138] (4) The step of preparing printing paste involves mixing hydrophilic modified silica microsphere powder with sodium carboxymethyl starch or sodium carboxymethyl cellulose, water, and inorganic alkali to obtain an easy-to-remove printing paste.

[0139] (4.1) The hydrophilic modified silica microsphere powder obtained in step (3.1), sodium carboxymethyl starch or sodium carboxymethyl cellulose, and water are mixed. The pH of the reaction system is controlled to be 10 to 10.5 with an inorganic alkali. After the mixture is fully stirred and gelatinized, the viscosity of the system is adjusted to 18000±500 mPa·s with a viscosity regulator to obtain an easy-to-remove printing paste.

[0140] The product prepared by the method of this invention can be used for the preparation of reactive dye printing pastes. It constructs a more easily elutable, strongly hydrophilic microphase aggregation region in the printing paste film, significantly improving the elutability of the printing paste. In this invention, the easily elutable printing paste not only ensures the relative concentration of the strongly hydrophilic microphase region, but its cross-linking structure also enhances the thickening ability of the printing paste without harming its rheological properties. This printing paste film with a physically "defective" structure provides a "breakthrough" for water to rapidly wet, penetrate, and elute the printing paste film during its soaping process, effectively enhancing the elution efficiency of the printing paste during soaping.

[0141] The easy-to-remove printing paste (viscosity 18000±500mPa·s) prepared in this embodiment has a paste formation rate of 5.9%, that is, sodium carboxymethyl starch accounts for 5.9% of the total mass of the prepared easy-to-remove printing paste; at the process viscosity (5000~6000mPa·s), the rheological index PVI of the paste is 0.20; the desizing rate is 96%. Desizing process: After the white paste-printed fabric is dried, it is washed once with hot water at 60℃ for 5 minutes, and then rinsed twice with room temperature water for 5 minutes each time. The amount of water used each time is 20 times the dry weight of the white paste-printed fabric.

[0142] Storage of products prepared by the method of this invention: The finished product must be sealed and stored in a cool, dry place.

[0143] Example 4

[0144] (1) Raw material preparation, the specific selection and amount of the raw materials are shown in Table 1;

[0145] (2) The printing paste was prepared using the same process and conditions as in Example 1.

[0146] The easy-to-remove printing paste (viscosity 17000±500mPa·s) prepared in this embodiment has a paste formation rate of 7.2%, that is, sodium carboxymethyl starch accounts for 7.2% of the total mass of the prepared easy-to-remove printing paste; at the process viscosity (5000~6000mPa·s), the rheological index PVI of the paste is 0.33; the desizing rate is 80%. Desizing process: After the white paste-printed fabric is dried, it is washed once with hot water at 60℃ for 5 minutes, and then rinsed twice with room temperature water for 5 minutes each time. The amount of water used each time is 20 times the dry weight of the white paste-printed fabric.

[0147] Test Example 1: Desizing rate indicates the degree to which the adhesive is removed from the fabric. A higher desizing rate means the adhesive is easier to remove, resulting in a softer fabric feel. The desizing rate is calculated using Formula 1:

[0148]

[0149] In Formula 1: m0 represents the mass of the fabric dried to constant weight before printing; m1 represents the mass of the fabric dried to constant weight after printing; m2 represents the mass of the printed fabric dried to constant weight after washing.

[0150] Test Example 2: Rheological Properties (PVI) A carboxymethyl starch paste with a viscosity of 5000±500 Pa·s was prepared for reactive printing. The viscosity at 6 rpm and 60 rpm was measured using an NDJ-5S rotational viscometer (rotor No. 4). The PVI value was calculated as shown in Formula 2.

[0151]

[0152] In Formula 2: η60 is the viscosity measured at 60 rpm; η6 is the viscosity measured at 6 rpm.

[0153] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing an easy-to-de-spread printing paste based on a microphase aggregation region with strong hydrophilicity in the film, characterized in that, Includes the following steps: (1) Raw material preparation: double bond silica balls, acrylic acid, silane coupling agent, initiator, composite solvent, sodium carboxymethyl starch or sodium carboxymethyl cellulose, water, inorganic alkali and viscosity modifier; The double bond content of the double bond silicon spheres is 0.2-1%, the particle size is 2-9 μm, and the particle size polydispersity index is 0.15-0.25; The silane coupling agent includes one of vinyltrimethoxysilane, methacryloyloxymethyltrimethoxysilane, 3-acryloyloxypropylmethyldimethoxysilane, and 3-methacryloyloxypropyltrimethoxysilane. The composite solvent is a mixed solution of deionized water and ethanol, and the mass fraction of ethanol in the composite solvent is 20-40%. The mass ratio of the double-bonded silicon spheres, acrylic acid, and silane coupling agent is 1:(2-5):(0.1-0.3), and the mass of the initiator is 1.5-3.5% of the total mass of the double-bonded silicon spheres, acrylic acid, and silane coupling agent. The mass ratio of sodium carboxymethyl starch or sodium carboxymethyl cellulose to the double-bonded silicon spheres is 50-150:

1. (2) Graft polymerization step: The double bonded silica spheres are reacted with acrylic acid, silane coupling agent and initiator in the composite solvent to obtain a hydrophilic modified silica microsphere dispersion; (3) Post-processing steps: The hydrophilic modified silica microsphere dispersion is filtered, dried and ground to obtain hydrophilic modified silica microsphere powder; (4) Steps for preparing printing paste: The hydrophilic modified silica microsphere powder is mixed with sodium carboxymethyl starch or sodium carboxymethyl cellulose, water and inorganic alkali to prepare an easy-to-remove printing paste.

2. The method according to claim 1, characterized in that, The mass of the composite solvent is 8 to 12 times the total mass of the double-bonded silicon spheres, acrylic acid, and silane coupling agent.

3. The method according to claim 1, characterized in that, The mass of the water is 8 to 12 times the mass of the sodium carboxymethyl starch or sodium carboxymethyl cellulose.

4. The method according to claim 1, characterized in that, The initiator includes one of ammonium persulfate and potassium persulfate; and / or, The water is soft water with a total hardness not exceeding 50 ppm CaCO3; and / or, The viscosity modifier is soft water with a total hardness not exceeding 50 ppm CaCO3; and / or, The inorganic base includes one or two of sodium hydroxide, sodium carbonate, and sodium bicarbonate.

5. The method according to claim 1, characterized in that, The pH value of the easily desizing printing paste constructed based on the strongly hydrophilic microphase aggregation region of the film is 9–11; and / or, The viscosity of the easy-to-de-dry printing paste constructed based on the strongly hydrophilic microphase aggregation region of the film is 15000-25000 mPa·s.

6. The method according to claim 1, characterized in that, The specific process of step (2) includes: (2.1) Add 60-80% of the total mass of the composite solvent, double bond silicon spheres, 30-60% of the total mass of acrylic acid, and 30-60% of the total mass of silane coupling agent into the reactor, mix, and control the system temperature at 70-80℃; (2.2) Mix the initiator, the remaining acrylic acid, the remaining coupling agent and the remaining composite solvent, and then, under stirring, at 70-80°C, uniformly drop the resulting mixture into the reactor over 60-90 minutes. (2.3) Under stirring, the material in the reactor is kept at 75-85℃ for 30-60 min to obtain a hydrophilic modified silica microsphere dispersion.

7. The method according to claim 1, characterized in that, The specific process of step (3) includes: The hydrophilic modified silica microsphere dispersion was filtered, and the resulting filter cake was vacuum dried. The dried filter cake was then ground to obtain hydrophilic modified silica microsphere powder.

8. The method according to claim 1, characterized in that, The specific process of step (4) includes: The hydrophilic modified silica microsphere powder, sodium carboxymethyl starch or sodium carboxymethyl cellulose, and water are mixed, and then an inorganic alkali is added to control the pH value of the system. After stirring and gelatinizing, a viscosity regulator is added to adjust the viscosity of the system to obtain an easy-to-release printing paste.

9. The easy-to-de-spread printing paste prepared by the method according to any one of claims 1-8, based on the construction of a microphase aggregation region with strong hydrophilicity in the film.

10. The application of the easy-to-remove printing paste based on the strongly hydrophilic microphase aggregation region of the paste film as described in claim 9 in fabric printing.

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