Digital inkjet three-dimensional printing ink and fabric three-dimensional printing method

Abstract

The embodiment of the application discloses a digital ink-jet three-dimensional printing ink and a fabric three-dimensional printing method. The ink comprises pigment ink and a fixing agent. The pigment ink comprises a colorant, a binder, a first additive and a first solvent. The binder comprises a water-based environment-friendly polymer. The fixing agent comprises an activator, an initiator, a second additive and a second solvent. The activator comprises at least one active component containing an amino functional group. Through a unique ink-jet printing material formula and a process method, the fixing agent and the binder are cross-linked at room temperature under the action of the initiator, forming an initial film layer. In the subsequent high-temperature baking and fixing process, the binder and the activator are dehydrated and condensed, the three-dimensional network cross-linked structure is accelerated to form and become stable, and the coating is completely cured and formed. The pattern with a three-dimensional effect can be obtained through ink-jet printing. The strong interface between the coating and the base material is combined, the adhesion grade is significantly improved, and the comprehensive performance of the coating is excellent.

Description

Technical Field

[0001] This application relates to the field of fabric printing technology, and in particular to a digital inkjet 3D printing ink and a method for 3D printing fabrics. Background Technology

[0002] Digital inkjet printing technology has become the dominant process technology in the textile printing field. With its significant advantages such as high pattern resolution, support for small-batch personalized customization, short production cycle, and green environmental protection (no wastewater discharge and low energy consumption), it is widely used in the printing and processing of various textile fabrics such as cotton, linen, silk, wool and chemical fibers, and has become an important technical support for the transformation and upgrading of the modern textile industry.

[0003] With the continuous upgrading of the consumer market and the increasing aesthetic demands of consumers, users have put forward higher-level technical requirements for textile printing effects. In addition to traditional basic quality indicators such as color vibrancy and pattern detail, consumers are increasingly demanding products with three-dimensional printing coatings that possess raised textures and visual depth. Products with three-dimensional effects can significantly enhance visual impact and increase product added value, showing broad application prospects in high-end clothing, home decoration, and functional textiles. However, existing textile inkjet printing technology still faces many technical bottlenecks in achieving three-dimensional printing effects. Its three-dimensional imaging capabilities are insufficient. Without additional physical or chemical post-processing steps such as embossing, flocking, and foaming, it is impossible to directly construct a highly gradient three-dimensional coating. Furthermore, these additional processes not only significantly increase the complexity of the production process, extend the production cycle, and increase manufacturing costs, but also easily lead to quality problems such as loss of pattern detail, decreased adhesion between the coating and the substrate, and poor stability of the three-dimensional structure, making it difficult to meet the industrial production needs of high-precision three-dimensional printing. Moreover, existing inkjet printing ink systems generally have poor compatibility with synthetic fiber substrates such as polyester fabrics.

[0004] In summary, existing textile inkjet printing technologies have significant shortcomings in terms of three-dimensional forming capabilities, substrate material compatibility, and overall coating performance, making it difficult to meet the market's technical demands for high-quality three-dimensional printed products. Therefore, there is an urgent need to develop a new inkjet printing material and application technology that can directly achieve three-dimensional effects, possesses good substrate compatibility, and exhibits excellent overall performance, in order to overcome existing technological bottlenecks and promote the innovative development of textile printing technology. Summary of the Invention

[0005] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a digital inkjet 3D printing ink and a 3D printing method for fabrics, so as to achieve a printing coating that can directly achieve a three-dimensional effect through inkjet printing, possessing good substrate compatibility and excellent overall performance.

[0006] In a first aspect, this application provides a digital inkjet 3D printing ink, comprising: pigment ink and a fixing agent; the pigment ink comprises a colorant, a binder, a first auxiliary agent and a first solvent, the binder comprising a water-based environmentally friendly polymer; the fixing agent comprises an activator, an initiator, a second auxiliary agent and a second solvent, the activator comprising at least one active component containing an amino functional group.

[0007] In some embodiments of the digital inkjet 3D printing ink described above, the colorant accounts for 5%-25% of the mass of the pigment ink; The binder accounts for 10%-40% of the mass of the pigment ink.

[0008] In some embodiments of the digital inkjet 3D printing ink described above, the colorant includes at least one of azo pigments, phthalocyanine pigments, and white paste pigments; The adhesive includes at least one of waterborne polyurethane, acrylate copolymers, and silicone-modified resins.

[0009] In some embodiments of the digital inkjet 3D printing ink described above, the first auxiliary agent includes surfactant, defoamer, and curing agent; The surfactant in the pigment ink accounts for 0.5%-4.0% by mass; The defoamer accounts for 0.5%-2.0% of the mass of the pigment ink; The curing agent accounts for 0.5%-5.0% of the mass of the pigment ink; The first solvent accounts for 30%-60% of the mass of the pigment ink.

[0010] In some embodiments of the digital inkjet 3D printing ink described above, the surfactant includes a nonionic surfactant; The defoamer includes at least one of silicone defoamers and acetylenic diol defoamers; The curing agent includes at least one of isocyanate curing agents and aziridine curing agents; The first solvent includes at least one of ethylene glycol, propylene glycol, and deionized water.

[0011] In some embodiments of the aforementioned digital inkjet 3D printing ink, the activator accounts for 0.5%-2.0% of the mass of the fixing agent; The activator includes at least one of multifunctional organic amines and alcoholic amines. The initiator accounts for 6%-10% of the mass of the fixing agent; The initiator includes at least one of lactic acid, acetic acid, boric acid, citric acid, and benzoic acid.

[0012] In some embodiments of the digital inkjet 3D printing ink described above, the second auxiliary agent includes an anti-yellowing agent and a wetting agent; The anti-yellowing agent accounts for 0.5%-2.0% of the mass of the fixing agent; The wetting agent comprises 1.5%-5.0% of the weight of the fixing agent; The second solvent accounts for 81%-91.5% of the mass of the fixing agent.

[0013] In some embodiments of the digital inkjet 3D printing ink described above, the anti-yellowing agent includes at least one of benzotriazole derivatives and epoxy resin polymers; The wetting agent includes at least one of propylene glycol derivatives; The second solvent includes at least one of ethylene glycol, propylene glycol, and deionized water.

[0014] Secondly, this application also provides a method for three-dimensional printing of fabrics, using digital inkjet three-dimensional printing ink as described in any one of the first aspects, the method comprising: A three-dimensional printed pattern is constructed by printing on a fabric substrate material based on a preset pattern and preset inkjet printing parameters at room temperature. Baking at 140℃-160℃ for 8-10 minutes allows the ink in the three-dimensional pattern to undergo a full chemical cross-linking reaction and solidify.

[0015] The above-described one or more embodiments of this application have at least one or more of the following beneficial effects: This application provides a digital inkjet 3D printing ink and a method for 3D printing on fabrics. The ink includes: pigment ink and a fixing agent; the pigment ink includes at least a colorant and a binder, the binder including a water-based environmentally friendly polymer; the fixing agent includes an activator and an initiator, the activator including at least one active component containing an amino functional group; through a unique inkjet printing material formulation and process, under the action of the initiator, the fixing agent and the binder can undergo a mild physical cross-linking reaction upon contact at room temperature to form an initial film layer. During the subsequent high-temperature baking and fixing process, the binder and the activator undergo dehydration condensation, accelerating the process. The three-dimensional cross-linked network structure is formed and stabilized, and the coating is completely cured and formed. It can directly obtain three-dimensional patterns through a single inkjet printing operation. The maximum three-dimensional height of the pattern can reach 1500μm, with distinct three-dimensional layers and outstanding visual effect. Through multiple interaction mechanisms between adhesives, fixing agents and chemical fibers (such as polyester fibers), a strong interfacial bond between the coating and the substrate material is achieved, and the adhesion level is significantly improved. At the same time, the key indicators of the coating, such as wear resistance, folding resistance and anti-yellowing performance, all reach or exceed level 4 (according to relevant national standards), and the overall performance is excellent.

[0016] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Detailed Implementation

[0017] The following describes some embodiments of this application. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of this application and are not intended to limit the scope of protection of this application.

[0018] As described in the background section, the current shortcomings of existing textile inkjet printing technology are mainly manifested in the following aspects: 1. Insufficient 3D forming capability. Traditional inkjet printing ink systems are mostly planar film-forming formulations, which can only form two-dimensional planar patterns after printing and curing. They cannot directly construct highly gradient 3D coatings, and can only achieve a weak 3D effect (coating thickness ≤ 50μm). To achieve a significant 3D effect (thickness > 50μm), additional physical or chemical post-processing steps such as embossing, flocking, and foaming must be introduced. These additional processes not only significantly increase the complexity of the production process, extend the production cycle, and increase manufacturing costs, but also easily lead to quality problems such as loss of pattern precision, decreased adhesion between the coating and the substrate, and poor stability of the 3D structure, making it difficult to meet the industrial production requirements of high-precision 3D printing.

[0019] 2. Existing inkjet printing ink systems generally have poor compatibility with synthetic fiber substrates such as polyester fabrics. Different types of synthetic fiber fabrics require separate ink formulations. Furthermore, current technologies have stringent requirements on the surface properties of the substrate material, limiting printing to planar or regular curved surfaces, and cannot meet the printing needs of slightly curved or complex three-dimensional curved substrates. Insufficient interfacial bonding strength between the printed coating and the substrate material easily leads to coating peeling, cracking, and other failures.

[0020] 3. Existing inkjet printing coatings have significant deficiencies in key performance indicators: abrasion resistance, folding resistance, yellowing resistance, as well as the washability and abrasion resistance of fabrics, do not meet industry standard requirements (all performance levels are <4). The mechanical durability of the coating (such as abrasion resistance and folding resistance) is low, making it difficult to meet the daily use requirements of textiles. During the high-temperature baking and color fixing process, the ink system is prone to thermal oxidation reaction, resulting in obvious yellowing, which seriously affects the appearance quality and service life of the product.

[0021] Furthermore, existing traditional inkjet printing inks require complex surface pretreatment of the printing substrate before use. For example, polyester fabrics require alkali reduction treatment to improve surface hydrophilicity; nylon and spandex fabrics require special degreasing treatment to remove impurities such as silicone oil from the fiber surface. This pretreatment process is cumbersome, time-consuming, inefficient, and generates wastewater pollution, which does not meet the requirements of green manufacturing.

[0022] The aforementioned technical defects severely restrict the application and expansion of chemical fiber fabrics and other functional fabrics in the field of high-end three-dimensional printing.

[0023] To address the aforementioned issues, this application creatively proposes a digital inkjet 3D printing ink and a method for 3D printing on fabrics. Through a unique digital inkjet 3D printing ink formulation and process, patterns with a three-dimensional effect can be obtained directly in a single inkjet printing operation. The maximum 3D height of the pattern can reach 1500μm, with distinct 3D layers and outstanding visual effects, significantly enhancing the artistic expression and added value of printed products. It exhibits strong material substrate compatibility, achieving a powerful interface bond between the coating and the substrate material, significantly improving adhesion levels. The overall performance indicators of the coating are improved. The production process is simple and efficient, requiring only inkjet printing and thermal curing, eliminating the need for pre-treatment and post-treatment of the substrate material. It requires low equipment investment, low energy consumption, a short production cycle, high production efficiency, and significantly reduces the unit product production cost, demonstrating promising prospects for industrial application and economic benefits.

[0024] The present application will be described in detail below through specific embodiments.

[0025] Specifically, this application provides a digital inkjet 3D printing ink, comprising: pigment ink and fixing agent; the pigment ink includes a colorant, a binder, a first auxiliary agent and a first solvent, the binder includes a water-based environmentally friendly polymer; the fixing agent includes an activator, an initiator, a second auxiliary agent and a second solvent, the activator includes at least one active component containing an amino functional group.

[0026] In this application, the term "waterborne environmentally friendly polymer" is abbreviated as waterborne polymer, which refers to polymeric materials that use water instead of organic solvents as the dispersion / dissolution medium. The molecular chains have hydrophilic groups and exist in the form of emulsions, aqueous solutions, or aqueous dispersions. They are virtually free of volatile organic pollutants, non-toxic, low-irritant, and non-flammable. Waterborne environmentally friendly polymers include at least one of water-dispersible emulsion polymers and water-soluble polymers. Water-dispersible emulsion polymers are suspended in water as tiny particles, which fuse into a continuous film after drying. Examples, not limitations, of water-dispersible emulsion polymers include waterborne acrylic emulsions, waterborne polyurethane emulsions, and waterborne epoxy emulsions. Water-soluble polymers have a large number of hydrophilic groups such as -COOH, -OH, and amide groups on their molecular chains and dissolve directly in water to form a transparent liquid. Examples, not limitations, of water-soluble polymers include polyvinyl alcohol (PVA), polyacrylamide, modified starch, and carboxymethyl cellulose.

[0027] As a preferred option, the waterborne environmentally friendly polymer includes at least one of waterborne polyurethane and acrylate copolymers. The aforementioned adhesives possess excellent film-forming properties, flexibility, and interfacial adhesion, and their glass transition temperature (T0) is [missing information]. g The temperature is controlled within the range of -20℃ to 10℃. The resulting coating has a dense structure and excellent mechanical properties, exhibiting good crack resistance. It can form a continuous and controllable thickness film structure on the surface of chemical fiber fabrics (preferably polyester fabrics) or other substrates, providing stable mechanical support for achieving three-dimensional effects. The acrylic copolymer adhesive also possesses excellent water resistance and abrasion resistance, exhibiting good compatibility and interfacial bonding strength with chemical fiber fabrics (especially polyester fabrics).

[0028] Colorants provide color, and adhesives and activators undergo a chemical reaction under the initiation of the initiator and high temperature conditions to form a three-dimensional cross-linked network structure. After heating and curing, a three-dimensional effect coating is obtained.

[0029] The fixing agent used in this application includes an activator, which comprises at least one active component containing an amino functional group (-NH2), forming a multi-component compound system with weak acidity. The amino functional group exhibits high chemical activity and can undergo a cross-linking reaction with the aqueous polymer of the adhesive to form a stable three-dimensional cross-linked network structure, significantly improving the mechanical properties and durability of the coating. Simultaneously, in aqueous solution, the amino functional groups (-NH2) on the fixing agent molecules can undergo partial protonation to form positively charged protonated amino groups (-NH3). + This protonated amino group can have a dual binding effect with the polar groups on the surface of pigment particles: on the one hand, it can interact with the carboxyl group (-COOH) to form a carboxylate group (-COO). - The pigment particles are primarily bonded by electrostatic attraction to form ionic bonds, and secondarily by secondary bonds such as hydrogen bonds with hydroxyl (-OH) groups, thus synergistically adsorbing them. This anchors the pigment particles stably within the coating system composed of the fixing agent and binder, effectively inhibiting pigment particle migration and detachment. Based on the above intermolecular bonding mechanism, and combined with the three-dimensional network spatial confinement effect formed by subsequent high-temperature cross-linking, the fixing agent system used in this application can significantly improve the adhesion of pigment particles to synthetic fiber fabrics, such as polyester fabrics, and other substrates. Simultaneously, this fixing agent system possesses excellent acid and alkali resistance and washability, does not damage the pigment's color development structure, has no adverse effect on the color performance of the printed pattern, and can maintain the color vibrancy and clarity of the pattern for a long time.

[0030] In the application of the digital inkjet 3D printing ink provided in this application, the adhesive and fixing agent, upon contact at room temperature, undergo a mild physical cross-linking reaction initiated by the initiator. The reaction kinetics are characterized by a slow rate and a mild, controllable degree, rapidly forming a thin and soft initial film layer, initially constructing a three-dimensional coating structure with soft properties. During subsequent heating and fixing, when the system temperature rises to 140℃ or above, the reaction kinetics significantly enhance, the cross-linking reaction proceeds rapidly, and a stable multiphase composite system is formed with the substrate material (such as polyester fabric) and pigment particles. Each reaction stage proceeds synergistically, and the specific mechanism is as follows: ① Room temperature instant film formation stage (from the time the pigment ink and fixing agent are mixed and come into contact until heating and fixing): During inkjet printing, after the pigment ink and fixing agent components are ejected from the printhead and come into contact with the substrate surface, the binder and fixing agent in the pigment ink undergo a gentle physical cross-linking reaction immediately under the initiation of the initiator (creating a weakly acidic environment). This process requires no external energy input, and the reaction kinetics are characterized by a slow rate, controllable degree, and no violent exothermic phenomena. At this stage, the amino groups (-NH2) on the activator in the fixing agent component reach protonation equilibrium at room temperature, partially converting into positively charged protonated amino groups (-NH3). +Simultaneously, the carboxyl groups (-COOH) in the adhesive molecules partially ionize into negatively charged carboxylate ions (-COO₂) under weakly acidic conditions. - The two form ionic bonds through electrostatic attraction, supplemented by a large number of intermolecular hydrogen bonds, which quickly achieves stable association between the binder, fixing agent and pigment particles, rapidly forming a thin and soft initial wet film, effectively reducing ink droplet bleeding, and initially constructing a three-dimensional pattern with "softness" characteristics.

[0031] ②High-temperature accelerated cross-linking stage (rapid reaction period): After printing, the substrate material for the printed coating is placed in a heating device and gradually heated. When the system temperature reaches 100℃, the moisture and solvent components in the coating gradually evaporate and are removed, the acidic environment in the coating continues to increase, and the ionic and hydrogen bonds formed at room temperature are further strengthened, achieving initial anchoring of the coating components on the fiber surface. Simultaneously, the increased temperature shifts the amino protonation equilibrium towards dissociation, partially protonating amino groups (-NH3). + The system releases nucleophilic free amino groups (-NH2), providing effective reaction sites for subsequent high-temperature covalent crosslinking reactions. At this temperature, the curing agent remains dormant and does not participate in the reaction, preventing uneven film formation caused by premature crosslinking. When the system temperature further increases to 140℃-160℃, residual moisture in the coating is essentially removed, the reaction kinetics rate significantly increases, and the crosslinking reaction enters a rapid phase. At this point, the dormant curing agent in the system is deactivated and activated with increasing temperature, becoming a crosslinking node that directly reacts with hydroxyl (-OH) and carboxyl (-COOH) groups in the adhesive molecules and amino groups (-NH2) in the fixing agent. It can also synergistically catalyze amidation and esterification reactions, significantly improving the crosslinking reaction rate and the density of the crosslinking network. Under the combined effects of high temperature, acidic catalysis, and curing agent activation, two types of core covalent reactions occur simultaneously: On the one hand, the free amino groups (-NH2) in the activator attack the carboxyl groups (-COOH) in the acid-activated adhesive molecules, undergoing a dehydration condensation reaction to generate a large number of stable amide bonds (-CONH-), achieving covalent bonding between the activator and the adhesive molecules; on the other hand, the hydroxyl groups (-OH) on the adhesive molecular chain undergo intermolecular esterification reactions with the carboxyl groups (-COOH), forming a self-crosslinking structure of the resin. Through the formation of these covalent bonds, the adhesive and activator molecules are firmly bonded to the fiber surface, jointly constructing a dense three-dimensional crosslinked network (see equations ① and ②). This three-dimensional cross-linked network structure has excellent rigidity and thermodynamic stability. As the "skeleton" structure of the three-dimensional coating, it provides stable mechanical support for the realization of the three-dimensional effect. At the same time, the cross-linked network structure can effectively encapsulate the pigment particles dispersed in the system in its internal cavity, preventing the pigment particles from migrating and falling off during subsequent use.

[0032] ③ High-temperature interfacial bonding strengthening stage (conducted simultaneously with the high-temperature accelerated cross-linking reaction): Under high-temperature conditions, the movement of adhesive molecular chains intensifies, leading to diffusion and entanglement to a certain extent into the microscopic cracks and amorphous regions on the surface of synthetic fibers (such as polyester fibers). Simultaneously, the hydrophobic segments in the adhesive molecules form stable hydrophobic interactions with the hydrophobic structures on the fiber surface, both enhancing the interfacial adsorption effect. As the internal cross-linking reaction of the coating progresses and the three-dimensional cross-linked network structure solidifies, the cured coating forms a stable "mechanical interlocking anchor" with the microscopic rough structure of the fiber surface. Through the synergistic effect of molecular entanglement, hydrophobic segment interaction, and mechanical interlocking, the interfacial bonding strength between the coating and synthetic fiber fabrics (preferably polyester fabrics) or other substrate materials can be significantly improved, forming a robust interfacial bonding system. This system achieves excellent adhesion and durability properties such as washability and abrasion resistance between the coating and the substrate material without requiring additional surface modification pretreatment such as plasma treatment or alkali reduction on the synthetic fiber fabric.

[0033] ④ Pigment fixation and strengthening stage (running through the entire process from room temperature to high temperature): At room temperature, the polar groups (such as -OH, -COOH, etc.) on the surface of the surface-modified pigment particles can initially adsorb and bind with the amino groups (-NH2) in the fixing agent molecules through secondary bonding forces such as hydrogen bonding and dipole-dipole interactions. Simultaneously, the soft initial film formed at room temperature physically encapsulates the pigment particles, initially achieving pigment fixation and reducing ink droplet bleeding. Upon entering the high-temperature stage, as the cross-linking reaction proceeds fully, the three-dimensional cross-linked network structure formed by the binder, activator, and curing agent continuously densifies, significantly enhancing the "spatial confinement" encapsulation effect on the pigment particles, becoming the core mechanism for pigment fixation. Although the secondary bonding effect temporarily weakens at high temperature, it can recover and synergistically function after cooling and curing. This mechanism effectively prevents pigment particles from detaching from the coating under external forces such as friction and washing, while avoiding blurring of pattern edges and "uniform dyeing" problems caused by pigment particle migration. It significantly improves the color fastness and color stability of the printed pattern, ensuring that the pattern maintains color vibrancy and clarity during long-term use.

[0034] ⑤ High-temperature reaction stabilization stage (stabilization period): This stage is the heat preservation period after the high-temperature rapid cross-linking reaction. At this time, the main cross-linking reaction is basically completed, the activation reaction of the curing agent at high temperature has been fully carried out, and the three-dimensional cross-linked network structure jointly constructed by the adhesive, activator, and curing agent has been formed. The coating has lost its fluidity and set. Under continuous high temperature conditions, the small amount of unreacted functional groups and residual curing agent in the system continue to complete the subsequent cross-linking reaction, further filling network defects and improving the compactness, uniformity, and cross-linking density of the three-dimensional cross-linked network structure. At the same time, the curing shrinkage internal stress inside the coating is gradually relaxed and released through the thermal motion of molecular chains, and the thermodynamic state of the system tends to stabilize. After this stage, the coating changes from a semi-cured state to a fully cured tough film layer, with comprehensive improvement in mechanical strength, durability, and long-term stability, ultimately forming a functional cured coating with excellent adhesion, stable three-dimensional structure, and balanced comprehensive performance.

[0035] In some embodiments, the colorant accounts for 5%-25% of the pigment ink by mass. Optionally, the colorant accounts for 5%, 7%, 9.5%, 13%, 15.6%, 19.3%, 20%, 22.1%, 25%, or any value within the above-mentioned mass percentage range. The binder accounts for 10%-40% of the pigment ink by mass. Optionally, the binder accounts for 10%, 13.5%, 17.2%, 20%, 24.6%, 28%, 33.4%, 37.5%, 40%, or any value within the above-mentioned mass percentage range. For the sake of space, this application will not elaborate further on this.

[0036] In some embodiments, the colorant includes at least one of azo pigments, phthalocyanine pigments, and white paste pigments; the binder includes at least one of waterborne polyurethane, acrylate copolymers, and silicone-modified resins.

[0037] In some embodiments, the first additive includes a surfactant, a defoamer, and a curing agent; the surfactant adjusts the surface tension of the ink, improving ink flow and wettability; the defoamer eliminates bubbles generated during ink preparation and inkjet printing; the curing agent acts as a "bridge" connecting the adhesive and the fixing agent, promoting the curing of the coating.

[0038] The surfactant accounts for 0.5%-4.0% of the pigment ink by mass. Optionally, the surfactant can account for 0.5%, 1.2%, 1.7%, 2.32%, 2.5%, 3.56%, 4.0%, or any value within the above mass percentage range. The defoamer accounts for 0.5%-2.0% of the pigment ink by mass. Optionally, the defoamer can account for 0.5%, 0.67%, 0.86%, 1%, 1.5%, 1.93%, 2.0%, or any value within the above mass percentage range. The curing agent accounts for 0.5%-5.0% of the pigment ink by mass. Optionally, the curing agent can account for 0.5%, 1.2%, 2.3%, 3.1%, 4.5%, 5.0%, or any value within the above mass percentage range. For space considerations, this application will not elaborate further on these aspects.

[0039] In some embodiments, the surfactant includes nonionic surfactants, including but not limited to one or more of fatty alcohol polyoxyethylene ether AEO-9, Tween-80, and hydrophobically modified ethylene oxide polyurethane copolymers. The defoamer includes at least one of silicone defoamers and acetylenic diol defoamers, including but not limited to one or more of polydimethylsiloxane, polyether-modified silicone, and butynediol. The curing agent includes at least one of isocyanate curing agents and aziridine curing agents, including but not limited to one or more of hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), toluene diisocyanate (TDI), and TTMP. The isocyanate groups (-NCO) in isocyanate curing agent molecules have low activity at room temperature, undergoing only trace reactions, thus stabilizing the mixed system (pigment ink and fixing agent composite system) and effectively preventing excessive crosslinking leading to film embrittlement. During the high-temperature accelerated crosslinking stage, the isocyanate groups (-NCO) are significantly activated, their chemical activity is greatly enhanced, and they rapidly participate in the construction of the crosslinking reaction network. The activated isocyanate curing agent acts as a crosslinking accelerator. The isocyanate groups (-NCO) in its molecule react with the hydroxyl groups (-OH) in the adhesive molecule to form urethane bonds, and undergo an addition reaction with the amino groups (-NH2) in the activator molecule to form urea bonds (-NH-CO-NH-), further promoting the transformation of the "flexible" crosslinking structure into a "rigid" three-dimensional crosslinking network structure (see equation ③). .

[0040] In some embodiments, the first solvent includes at least one of ethylene glycol, propylene glycol, and deionized water. The first solvent is used to adjust the ink viscosity and the wetting properties of the substrate fabric. The mass percentage of the first solvent in the pigment ink is 30%-60%. Optionally, the mass percentage of the first solvent in the pigment ink can be 30%, 35%, 39%, 41%, 43%, 46.4%, 50%, 56.7%, 60%, or any value within the above mass percentage range. For the sake of space, this application will not elaborate further.

[0041] In some embodiments, the activator accounts for 0.5%-2.0% of the mass of the fixing agent. Optionally, the mass percentage of the activator in the fixing agent can be 0.5%, 0.65%, 0.82%, 1.0%, 1.34%, 1.55%, 1.9%, 2.0%, or any value within the above mass percentage range. For space considerations, this application will not elaborate further. The activator includes at least one of multifunctional organic amines and alkanolamines, including but not limited to one or more of p-aminobenzoic acid, o-aminophenol, p-aminophenol, 2-amino-2-methyl-1-propanol, 2-amino-2-hydroxymethyl-1,3-propanediol, glycine, and glutamic acid. The activator provides active amino functional groups, undergoes a cross-linking reaction with the adhesive to form a three-dimensional cross-linked network structure; forms weak interaction forces with pigment particles through hydrogen bonding, coating the pigment particles and reducing their migration or shedding; and improves the bonding strength between the coating and the polyester fabric. The initiator accounts for 6%-10% of the weight of the fixing agent. Optionally, the weight percentage of the initiator in the fixing agent can be 6%, 7.5%, 8.24%, 9.07%, 9.5%, 10%, or any value within the above weight percentage range. The initiator includes at least one of lactic acid, acetic acid, boric acid, citric acid, and benzoic acid, providing acidic conditions for the reaction between the adhesive and the activator to initiate the reaction; it also has antibacterial properties that inhibit the growth of bacteria, fungi, and other microorganisms, extending the product's service life.

[0042] In some embodiments, the second additive includes an anti-yellowing agent and a wetting agent. The anti-yellowing agent absorbs ultraviolet light, blocks the photo-oxidation chain reaction, and improves the anti-yellowing performance of the coating. The anti-yellowing agent accounts for 0.5%-2.0% of the weight of the fixing agent. Optionally, the weight percentage of the anti-yellowing agent in the fixing agent can be 0.5%, 0.67%, 0.83%, 1.0%, 1.32%, 1.5%, 1.67%, 2.0%, or any value within the above weight percentage range. The wetting agent adjusts the wettability of the fixing agent to the substrate material and improves the pattern fineness. The wetting agent accounts for 1.5%-5.0% of the weight of the fixing agent. Optionally, the weight percentage of the wetting agent in the fixing agent can be 1.5%, 2.3%, 3.55%, 4.3%, 4.56%, 5.0%, or any value within the above weight percentage range.

[0043] In some embodiments, the anti-yellowing agent includes at least one of benzotriazole derivatives and epoxy resin polymers, by way of example only and not limitation. The anti-yellowing agent includes one or more of 5-carboxybenzotriazole, methylbenzotriazole, 2,6-di-tert-butyl-4-methylphenol, 4,4'-hexamethylenebis(1,1-dimethylaminourea), and diglycidyl phthalate (TGDDM). The wetting agent includes propylene glycol derivatives, by way of example only and not limitation. The wetting agent includes one or more of dipropylene glycol, dipropylene glycol methyl ether, and dipropylene glycol butyl ether.

[0044] In some embodiments, the second solvent includes at least one of ethylene glycol, propylene glycol, and deionized water. The second solvent adjusts the viscosity and wettability of the fixing agent. The mass percentage of the second solvent in the fixing agent is 81%-91.5%. Optionally, the mass percentage of the second solvent in the pigment ink can be 81%, 83%, 84%, 85%, 86%, 91%, 91.5%, or any value within the above mass percentage range. For the sake of space, this application will not elaborate further.

[0045] This application also provides a method for three-dimensional printing of fabrics, using digital inkjet three-dimensional printing ink as described in any of the above embodiments, the method comprising: S110. Print on a fabric substrate material at room temperature based on a preset pattern and preset inkjet printing parameters to construct a three-dimensional printed pattern.

[0046] S120, bake at 140℃-160℃ for 8-10 minutes to fix the color, so that the ink in the three-dimensional pattern can fully undergo chemical cross-linking reaction and solidify into shape.

[0047] The reaction kinetics between the binder and the fixing agent in the digital inkjet 3D printing ink provided in this application are mainly affected by the heat treatment temperature and time. Under the process conditions adopted in this application (140℃-160℃, 8min-10min), the reaction kinetics are controllable and stable. Specifically: At room temperature (25℃), the fixing agent and adhesive undergo a mild physical cross-linking reaction upon contact, with a slow reaction rate, initially forming a thin and soft film. During the high-temperature baking stage (140℃-160℃), as the system temperature increases, molecular thermal motion intensifies, and reaction kinetics significantly improve. The adhesive and activator rapidly undergo dehydration condensation, while the curing agent accelerates the formation of the three-dimensional cross-linked network structure, strengthening the overall mechanical properties of the cross-linked network. The adhesive and polyester fibers achieve a strong bond through hydrophobic interactions and "mechanical interlocking and anchoring," with pigment particles tightly encapsulated by the three-dimensional cross-linked network structure formed by the adhesive, activator, and curing agent. In the high-temperature stabilization stage, the reaction rate gradually slows down, and the remaining unreacted components in the system continue to react, causing the three-dimensional cross-linked network structure to approach a thermodynamically stable state, and the coating to completely cure and solidify.

[0048] Temperature has a significant impact on reaction kinetics: as temperature increases, the reaction rate accelerates. For example, at 160℃, the rapid reaction period can be shortened to 1-4 minutes, requiring only 4 minutes to complete more than 80% of the crosslinking reaction, achieving rapid curing of the coating; as temperature decreases, the reaction rate slows down accordingly. For example, at 140℃, it takes 6 minutes to complete the entire crosslinking reaction, ensuring sufficient curing and stable performance of the coating.

[0049] The mass ratio of pigment ink to fixing agent is (1-9):1. Optionally, the mass ratio of pigment ink to fixing agent can be 1:1, 2.5:1, 4:1, 6.4:1, 8.2:1, 9:1, or any ratio within the above range. For space considerations, this application will not elaborate further. The ratio of binder to fixing agent has a significant impact on reaction kinetics. When the mass ratio of binder to fixing agent is controlled within the range of 9:1 to 1:1, the reaction kinetics are optimal, the crosslinking reaction is most complete, and the overall performance of the resulting coating reaches its best state.

[0050] It should be noted that the term "Pass number" refers to the total number of times the print head scans back and forth across the same unit area of ​​the fabric. The Pass number is 1-16, and optionally, it can be 1, 3, 5, 8, 10, 12, 14, 16, or any value within the above range.

[0051] In one specific implementation, the method includes: a. Pigment ink preparation and purification: Mix the components of the pigment ink in proportion, stir evenly to form a stable dispersion, filter to remove impurities and large particles, ensure smooth printing process, avoid clogging the printhead, and obtain pigment ink that can be used for inkjet printing.

[0052] b. Preparation and purification of the fixing agent: Mix the components of the fixing agent in proportion, stir evenly to form a stable, colorless and transparent solution, filter to remove impurities, ensure smooth printing process, avoid clogging the printhead, and obtain a fixing agent that can be used for inkjet printing.

[0053] c. Printing preparation: Load the pre-treated pigment ink and fixing agent into different ink cartridges of the inkjet printer. Adjust the inkjet printer parameters (such as ink volume, pigment ink to fixing agent ratio, number of passes, inkjet rate, etc.) according to the required 3D height and shape of the printed pattern to ensure precise control of the printing process and accurate realization of the 3D effect.

[0054] d. Inkjet printing: Fix the polyester fabric or other substrate material onto the printing platform of the inkjet printer, start the printer, and print according to the preset pattern. By controlling the ink volume, number of passes, inkjet rate and other process parameters of the inkjet printer, the gradient height distribution of the three-dimensional pattern in the vertical direction can be achieved to create a printed pattern with a three-dimensional effect.

[0055] e. Color fixing (baking) treatment: After printing, the printed coated fabric is transferred to a heating device for color fixing treatment. Under preset temperature (preferably 140℃-160℃) and time (preferably 8min-10min) conditions, the components in the inkjet ink system undergo a full chemical cross-linking reaction, achieving complete curing and molding of the coating, and finally obtaining a functional printed fabric product with excellent three-dimensional effect, high color fastness and good durability.

[0056] The present application will be further described in detail below through specific embodiments. The embodiments are only used to explain the present invention and are not intended to limit the scope of protection of the present invention.

[0057] The tests conducted in this application include: Wash fastness test: GB / T 3921-1997 Textiles - Tests for color fastness to washing (US standard: AATCC 61 Wash fastness to washing; US standard can be added if necessary) Colorfastness to rubbing test: GB / T 3920-2024 Textiles - Tests for colorfastness to rubbing; Martindale abrasion resistance test: GB / T 21196.1-21196.4 Textiles - Martindale method for testing the abrasion resistance of fabrics; Flexural strength test: GB / T 39368-2020 Physical and mechanical tests of leather - Determination of flexural strength: Upper bending method; Yellowing resistance test: "GB / T 30669-2014 Textiles - Tests for color fastness - Color fastness to light yellowing" and "GB / T29778-2013 Textiles - Tests for color fastness - Evaluation of potential phenolic yellowing".

[0058] Example 1: This example provides a digital inkjet 3D printing ink and a method for 3D printing on fabrics. The 3D printing ink includes pigment ink and a fixing agent. The components of the pigment ink and the fixing agent are shown in Table 1 and Table 2 by mass percentage. Table 1 Table 2 The specific steps for applying the above materials are as follows: a. Pigment ink preparation and purification: Mix the components of the pigment ink in proportion, stir evenly to form a stable dispersion, filter to remove impurities and large particles, ensure smooth printing process, avoid clogging the printhead, and obtain pigment ink that can be used for inkjet printing.

[0059] b. Preparation and purification of the fixing agent: Mix the components of the fixing agent in proportion, stir evenly to form a stable, colorless and transparent solution, filter to remove impurities, ensure smooth printing process, avoid clogging the printhead, and obtain a fixing agent that can be used for inkjet printing.

[0060] c. Printing Preparation: Load the pre-treated pigment ink and fixing agent into different ink cartridges of the inkjet printer. The components of the pigment ink and fixing agent in Tables 1 and 2 should be combined and used according to the combinations in Table 3. Adjust the inkjet printer parameters as shown in Tables 3-1, 3-2, 3-3 and 3-4 according to the required 3D height and shape of the printed pattern to ensure precise control of the printing process and accurate realization of the 3D effect.

[0061] Table 3-1 Table 3-2 Table 3-3 Table 3-4 d. Inkjet printing: Fix the polyester fabric or other substrate material onto the printing platform of the inkjet printer, start the printer, and print the inkjet pattern according to the preset pattern. By controlling the ink volume, printing speed, inkjet rate and other process parameters of the inkjet printer (where the number of passes is the number of coating prints), the gradient height distribution of the three-dimensional pattern in the vertical direction can be achieved to create a printed pattern with a three-dimensional effect.

[0062] e. Color Fixing (Baking) Treatment: After printing, the printed fabric is transferred to a heating device for color fixing treatment. Under preset conditions (150℃, 8min), the components in the inkjet ink system undergo a full chemical cross-linking reaction, achieving complete curing and molding of the coating, and finally obtaining a functional printed fabric product with excellent three-dimensional effect, high color fastness and good durability.

[0063] System performance tests were conducted on fabric samples after inkjet printing. The test results showed that the prepared three-dimensional printed coating can achieve a continuously adjustable and uniform raised height. By precisely controlling the geometric shape of the digital pattern and the number of inkjet printing layers, the height of the printed coating can be precisely controlled within the range of 10μm-1500μm. Specific height gradients include multiple precise control nodes such as 10μm, 50μm, 100μm, 200μm, 300μm, 400μm, 500μm, 600μm, 700μm, 800μm, 900μm, 1000μm, 1100μm, 1200μm, 1300μm, 1400μm, and 1500µm. The control accuracy is high and the repeatability is good.

[0064] As shown in Tables 3-1, 3-2, 3-3, and 3-4, the three-dimensional coating obtained by the ink combination printing provided in this embodiment exhibits excellent pattern fineness, with clear and sharp pattern edges, rich detail levels, and no blurring, diffusion, or distortion. The coating surface has high flatness, no obvious defects, significant three-dimensional effect, and strong visual expression. The coating has good durability (abrasion resistance and flexural strength are both ≥3 levels), and exhibits excellent interfacial bonding strength between the coating and the substrate material. After testing, the coating showed no peeling, flaking, or cracking, demonstrating high interfacial bonding strength and meeting the requirements for highly functional textiles. The printed fabric shows no color bleeding or fading under use scenarios such as friction and washing (color fastness to rubbing and washing both reach or exceed 3 levels), exhibiting excellent color retention. The printed fabric does not fade or deform after long-term use, demonstrating good durability and appearance retention.

[0065] In Example 1, compared to the at least four independent processes of traditional four-color offset printing combined with embossing, Example 1 only includes two processes (inkjet printing + heat drying), and the resulting 3D printed pattern can have a raised height ranging from 10 μm to 1500 μm. In contrast, the highest raised height of a pattern produced by traditional processes is only 50 μm, and precise control is impossible. For the minimum order quantity, Example 1 uses only one sheet, resulting in near-zero cost proofing. Traditional processes typically require thousands of sheets, leading to high proofing costs and long lead times. Furthermore, Example 1 produces extremely high pattern precision, capable of printing complex gradients and finely detailed embossed patterns. Traditional processes, on the other hand, have low pattern precision, with the embossed area consisting of large color blocks, making fine adjustment impossible. Additionally, Example 1 is applicable to flat and slightly curved substrates, while traditional processes are limited to flat or regularly curved surfaces, restricting their application range. For a detailed comparison, please refer to Table 4 below.

[0066] Table 4 Project Comparison 1 Example 2: The difference between this example and Example 1 is that the printing is performed on a mesh fabric. The 3D printing ink includes pigment ink and a fixing agent. The components of the pigment ink and the fixing agent are expressed as a percentage by mass. The specific printing parameters are shown in Tables 5 and 6, respectively. Table 5 Table 6 The specific steps for applying the above materials are as follows: a. Preparation and purification of pigment ink: Mix the above components (except for pigment and curing agent) in proportion, disperse at high speed to form a uniform dispersion system, then add pigment and stir at high speed to obtain a uniform dispersion liquid. Finally, slowly add curing agent and stir evenly to obtain a stable uniform dispersion liquid. Filter through a 1 µm filter membrane to remove impurities and large particles to obtain inkjet ink suitable for inkjet printing; b. Preparation and purification of the fixing agent: Mix the components of the fixing agent in proportion, stir evenly to form a stable, colorless and transparent solution, filter to remove impurities, ensure smooth printing process, avoid clogging the printhead, and obtain a fixing agent that can be used for inkjet printing.

[0067] c. Printing preparation: Load the pre-treated pigment ink from Table 5 and the fixing agent from Table 6 into the different ink cartridges of the inkjet printer according to the combinations shown in Table 7. Adjust the inkjet printer parameters (such as ink volume, pigment ink to fixing agent ratio, number of passes, inkjet rate, print speed, etc.) according to the required 3D height and shape of the printed pattern to ensure precise control of the printing process and accurate realization of the 3D effect.

[0068] Table 7 d. Inkjet printing: Fix the polyester mesh fabric on the printing platform of the inkjet printer, start the printer, and print according to the preset pattern. According to the printing height requirements, refer to Table 7 to control the ink volume, pigment ink to fixing agent ratio, number of passes (number of coating prints), and printing speed of the inkjet printer to achieve a gradient height distribution of the three-dimensional pattern in the vertical direction and construct a printed pattern with a three-dimensional effect.

[0069] e. Color fixing (baking) treatment: After printing, the mesh polyester fabric with the printed coating is transferred to a heating device for color fixing treatment. First, it is pre-baked at 80℃ for 2 minutes, and then baked at 150℃ for 8 minutes to allow the components in the ink system to fully undergo chemical cross-linking reaction, so as to achieve complete curing and molding of the coating, and finally obtain a coated fabric with excellent three-dimensional effect.

[0070] The inkjet printing achieved precise deposition on the mesh-structured polyester fabric, with no ink penetration at the edges or on the back of the fabric. The pattern outlines were clear, sharp, and well-defined. The resulting three-dimensional coating structure was uniform and consistent, with a clearly discernible surface texture and a raised coating height of approximately 1000µm, resulting in a soft and comfortable feel. The fabric treated with the printing coating retained its excellent breathability and flexibility, without compromising its original wearing comfort and functionality.

[0071] Systematic performance tests were conducted on fabric samples treated with the printed coating. Test results showed that key indicators such as abrasion resistance, flexural strength, and anti-yellowing properties of the printed-coated fabric all met or exceeded Level 3 standards (based on relevant national standards). After water washing performance testing according to AATCC 61-2020 2A standard, the three-dimensional structure of the coating on the fabric surface remained intact, with no defects such as color difference, cracking, or peeling. The color fastness to washing and rubbing (including dry and wet rubbing) of the printed-coated fabric both met or exceeded Level 3 standards, demonstrating excellent durability and color stability.

[0072] Mesh fabrics have numerous pores, making them susceptible to ink penetration and contamination on the back side using traditional inks. Furthermore, the fabric's softness and frequent bending and washing necessitate coatings with excellent flexibility and adhesion. Achieving impermeable, high-fastness, and three-dimensional digital printing is extremely challenging. The digital printing ink used in Example 2 is impermeable. The ink is precisely deposited on the surface of the mesh fibers without back-side leakage, resulting in a clear pattern outline and a distinct, uniform black raised texture with a height of approximately 300-500 μm, providing a noticeable tactile feel. In terms of feel and performance, the softness of the printed coated fabric does not affect the fabric's breathability and flexibility. Following AATCC 61-2020 2A standard, after 30 washes, the raised texture remained intact, with no color difference, cracking, or peeling, and the dry rubbing fastness reached level 3 or higher. See Table 8 below for a detailed comparison.

[0073] Table 8 Project Comparison II Example 3: The difference between this example and Example 1 is that the printing is performed on sandwich fabric. The 3D printing ink includes pigment ink and a fixing agent. The components of the pigment ink and the fixing agent are expressed as a percentage by mass. The specific printing parameters are shown in Tables 9 and 10. Table 9 Table 10 The specific steps for applying the above materials are as follows: a. Preparation and purification of pigment ink: The above components (except pigment particles and curing agent) are mixed in proportion and dispersed at high speed to form a uniform dispersion system. Pigment particles are then added, and the mixture is stirred at high speed to obtain a uniform dispersion. Finally, the curing agent is slowly added, and the mixture is stirred until a stable uniform dispersion is obtained. The dispersion is then ground using a ceramic nano-grinding mill until the particle size is ≤1µm. Finally, it is filtered through a 1µm filter membrane to remove impurities and large particles, yielding an inkjet ink suitable for inkjet printing. b. Preparation and purification of the fixing agent: Mix the components of the fixing agent in proportion, stir evenly to form a stable, colorless and transparent solution, filter 1µm to remove impurities, ensure smooth printing process, avoid clogging the printhead, and obtain a fixing agent that can be used for inkjet printing.

[0074] c. Printing preparation: Load the pre-treated pigment ink and fixing agent into different ink cartridges of the inkjet printer according to the combination in Table 11. Adjust the inkjet printer parameters (such as ink volume, pigment ink to fixing agent ratio, number of passes, inkjet rate, print speed, etc.) according to the required 3D height and shape of the printed pattern to ensure precise control of the printing process and accurate realization of the 3D effect.

[0075] Table 11 d. Inkjet printing: Fix the sandwich polyester fabric on the printing platform of the inkjet printer, start the printer, and print the inkjet pattern according to the preset pattern. According to the printing height requirements, refer to Table 11 to control the ink volume, pigment ink to fixing agent ratio, number of passes (printing passes), inkjet rate and spray speed of the inkjet printer, etc., to achieve the gradient height distribution of the three-dimensional pattern in the vertical direction and build a printed pattern with a three-dimensional effect. e. Color fixing (baking) treatment: After printing, the sandwich polyester fabric with the printed coating is transferred to a heating device for color fixing treatment. First, it is pre-baked at 80℃ for 3 minutes, and then baked at 150℃ for 7 minutes to allow the components in the ink system to fully undergo chemical cross-linking reaction, so as to achieve complete curing and molding of the coating, and finally obtain a coated fabric with excellent three-dimensional effect.

[0076] System performance tests were conducted on fabric samples after inkjet printing according to the above embodiments. The test results showed that the prepared three-dimensional printed coating can achieve a continuously adjustable and uniform raised height. By precisely controlling the geometric shape of the digital pattern and the number of inkjet printing layers and other process parameters, the height of the printed coating can be precisely and digitally controlled within the range of 10μm-800μm. Specific height gradients include multiple precise control nodes such as 10μm, 50μm, 100μm, 200μm, 300μm, 400μm, 500μm, 600μm, 700μm, and 800μm. The control accuracy is high and the repeatability is good.

[0077] The resulting 3D coating exhibits excellent pattern precision, with sharp, clear edges, rich detail, and no blurring, diffusion, or distortion. The coating surface is highly smooth, free of obvious defects, and displays a striking 3D effect with strong visual appeal. The coating demonstrates good durability (abrasion resistance and flexural strength both ≥3 levels), exhibiting excellent interfacial bonding strength with the substrate material. After testing, the coating showed no peeling, flaking, or cracking, demonstrating high interfacial bonding strength and meeting the requirements for highly functional textiles. The printed fabric shows no color bleeding or fading under conditions such as friction and washing (both rubbing and washing fastness reach or exceed 3 levels), exhibiting excellent color retention. The printed coated fabric retains its pattern without fading or deformation over long-term use, demonstrating good durability and appearance retention. A detailed comparison with traditional processes can be found in Table 12 below.

[0078] Table 12 Item Comparison II Comparative Example 1: This comparative example uses traditional printing ink. The components and proportions of the printing ink are shown in Table 13: Table 13 Comparative Example 2: This comparative example uses traditional printing ink. The components and proportions of the printing ink are shown in Table 14: Table 14 Comparative Example 3: The ink components and ratios used in this comparative example are shown in Table 15: Table 15 Comparative Example 4: The ink components and ratios used in this comparative example are shown in Table 16: Table 16 Comparative Examples 1-4 used traditional inkjet printing inks, which were pigment inks and did not require fixing agents.

[0079] Pigment inks were prepared according to Tables 13 and 14, and large particulate impurities were removed by filtration through a 1µm filter membrane to obtain inks suitable for inkjet printing. The inks were then printed onto polyester-cotton blended fabrics. A blower-type heating oven was used to heat and cure the printed coating on the polyester-cotton blended fabric at 130℃ for 3 minutes. Performance tests were then conducted. The results showed that the coating's folding resistance and abrasion resistance were both grade 3, and its anti-yellowing grade was 4. The printed coating was almost flat (with little three-dimensional effect), with a height ≤50μm. After heating and drying, the printed fabric felt noticeably harder. After standard rubbing and washing tests, the wet rubbing fastness was grade 3, and some of the coating showed discoloration after 15 washes, failing to meet daily use requirements.

[0080] According to Tables 15 and 16, the components (except for the pigment) are mixed in proportion and stirred evenly using a top-mounted stirrer. After high-speed dispersion at 1500 rpm for 20 minutes, a uniform dispersion system is formed. The speed is then reduced to 200 rpm, and the pigment is slowly added. The stirring speed is adjusted to 600 rpm until a uniform dispersion is obtained. The dispersion is then ground using a ceramic nano-grinding mill until the particle size is ≤1µm. Impurities and large particles are removed by filtering through a 1µm filter membrane to obtain inkjet printing ink. The ink is directly printed onto a polyester-cotton blended fabric. The printed polyester-cotton blended fabric is then heated and cured using an infrared conveyor belt dryer at 160℃ for 60 seconds. Subsequent performance tests revealed that the coating's folding resistance met the standard (level 4), but its abrasion resistance was poor (level 2 only). The yellowing resistance level was between 3 and 4, and the fabric showed slight yellowing. The three-dimensional effect of the printed coating was not significant, with a maximum height of ≤150μm. After heating and drying, the printed fabric felt stiff. After standard rubbing and washing tests, the color fastness to rubbing met the standard (level 4), but the washing resistance did not meet the standard. After 20 washes, the coating color faded significantly, the edges of the pattern became blurred, and cracks appeared in some areas, failing to meet the requirements for high-end textile materials.

[0081] Comparative Example 5: The ink components and ratios used in this comparative example are shown in Table 17: Table 17: This comparative example involves adjusting the pigment ink composition. The pigment ink was prepared according to Table 17, using a fixing agent with the same components as in Table 2 1A of Example 1, resulting in an ink suitable for inkjet printing. The ink was then printed onto fabric using the same printing parameters and steps as in Example 1, followed by performance testing. The results showed that in Comparative Example 5.1, due to the absence of colorant components, the printed coating was a colorless and transparent film, resulting in low pattern resolution, unclear boundaries, and a lack of significant three-dimensional effect (height < 50). In Comparative Example 5.2, when the colorant ratio was too low (4%), the coating's folding and washing resistance were poor (level 3). After 20 washes, the coating color faded significantly, the printed coating lacked a three-dimensional effect with a maximum height of <20μm, the printed coating had low resolution, a blurry pattern, and ink bleeding. Multiple prints did not result in any coating buildup. In Comparative Example 5.3, when the colorant ratio was too high (28%), the coating's folding and abrasion resistance were poor (level 3), and the washing resistance was substandard (level 2). The printed coating had a certain three-dimensional height, with a maximum height of ≤300μm, but the pigment particles in the coating were not completely fixed, resulting in discoloration. In Comparative Example 5.4, due to the lack of binder components, the ink completely diffused and permeated to the surrounding area after printing, resulting in a blurry, almost flat pattern with a height of <5μm. In Comparative Example 5.5, when the adhesive ratio was too low (8%), the abrasion resistance of the coating was poor (only level 2), and the coating peeled off. The printed pattern boundaries were blurry, and the coating did not have a stacking effect after multiple printings, with the highest height being <10μm. In Comparative Example 5.6, when the adhesive ratio was too high (48%), ink clogging occurred during printing, the folding resistance of the coating was poor (level 3), and the printed coating had a certain three-dimensional height, with the highest height being ≤140μm. However, the coating felt hard to the touch, and after long-term use, the coating was prone to cracking and slight yellowing, all of which did not meet the product usage requirements.

[0082] Comparative Example 6: The ink components and ratios used in this comparative example are shown in Table 18: Table 18: This comparative example involves adjustments to the fixing agent components. The fixing agent was prepared according to Table 15 and used in Example 1. 1a Pigment inks with the same components were prepared to obtain inks suitable for inkjet printing. Using the same printing parameters and steps as in Example 1, the inks were printed onto fabric, and performance tests were subsequently conducted. The results showed that: In Comparative Example 6.1, due to the absence of an activator component, the coating film formation was poor, and the adhesion to the fabric was weak. During the abrasion test, the coating peeled off over a large area (only level 2-3). During the folding test, the coating showed obvious cracks (only level 2). The rubbing fastness was only level 2. After washing, the printed coated fabric had a lot of floating color, and the washing fastness was level 2. In Comparative Example 6.2, when the activator ratio was too small (0.4%), the coating's abrasion resistance was poor (only level 2), and the coating peeled off during the abrasion test. The yellowing resistance level was between 3-4, the fabric showed slight yellowing, the printed coating boundary was unclear, ink bleeding occurred, and the coating surface was uneven. In Comparative Example 6.3, when the activator ratio was too large (4%), the coating's abrasion resistance was insufficient (level 3-4), and the printed coating surface had unevenness. The coating exhibited some cracks after folding endurance testing, indicating poor durability. Comparative Example 6.4, lacking an initiator component, showed an uneven surface after high-temperature baking and poor adhesion to the fabric. During abrasion testing, a large area of ​​the coating completely peeled off (grade 2-3). During folding endurance testing, the colorant showed significant peeling, and the coating exhibited severe cracking (grade only 2). Washing resistance was poor (grade only 2-3). Furthermore, the anti-yellowing agent component was excessive (3.2%), causing the fabric to yellow slightly after high-temperature baking. In Comparative Example 6.5, when the initiator ratio was too small (4%), the printed coating had poor abrasion resistance, with pigment particles falling off during the abrasion test. The water washability was poor (only 3), and there were fading and staining problems after washing. In Comparative Example 6.6, when the initiator ratio was too large (14%), the printed coating had a hard feel, with obvious cracks in some areas of the coating surface. The coating showed obvious "cracking" during the folding test, and the folding strength was only about 2, all of which did not meet the product use requirements.

[0083] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0084] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0085] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A digital inkjet 3D printing ink, characterized in that, include: Pigment ink and fixing agent; the pigment ink includes a colorant, a binder, a first auxiliary agent and a first solvent, the binder including a water-based environmentally friendly polymer; the fixing agent includes an activator, an initiator, a second auxiliary agent and a second solvent, the activator including at least one active component containing an amino functional group.

2. The digital inkjet 3D printing ink according to claim 1, characterized in that, The colorant in the pigment ink accounts for 5%-25% by mass; The binder accounts for 10%-40% of the mass of the pigment ink.

3. The digital inkjet 3D printing ink according to claim 1 or 2, characterized in that, The colorant includes at least one of azo pigments, phthalocyanine pigments, and white paste pigments; The adhesive includes at least one of waterborne polyurethane, acrylate copolymers, and silicone-modified resins.

4. The digital inkjet 3D printing ink according to claim 1, characterized in that, The first additive includes surfactants, defoamers, and curing agents; The surfactant in the pigment ink accounts for 0.5%-4.0% by mass; The defoamer accounts for 0.5%-2.0% of the mass of the pigment ink; The curing agent accounts for 0.5%-5.0% of the mass of the pigment ink; The first solvent accounts for 30%-60% of the mass of the pigment ink.

5. The digital inkjet 3D printing ink according to claim 4, characterized in that, The surfactants include nonionic surfactants; The defoamer includes at least one of silicone defoamers and acetylenic diol defoamers; The curing agent includes at least one of isocyanate curing agents and aziridine curing agents; The first solvent includes at least one of ethylene glycol, propylene glycol, and deionized water.

6. The digital inkjet 3D printing ink according to claim 1, characterized in that, The activator accounts for 0.5%-2.0% of the mass of the fixing agent; The activator includes at least one of multifunctional organic amines and alcoholic amines. The initiator accounts for 6%-10% of the mass of the fixing agent; The initiator includes at least one of lactic acid, acetic acid, boric acid, citric acid, and benzoic acid.

7. The digital inkjet 3D printing ink according to claim 1 or 6, characterized in that, The second adjuvant includes anti-yellowing agents and wetting agents; The anti-yellowing agent accounts for 0.5%-2.0% of the mass of the fixing agent; The wetting agent comprises 1.5%-5.0% of the weight of the fixing agent; The second solvent accounts for 81%-91.5% of the mass of the fixing agent.

8. The digital inkjet 3D printing ink according to claim 7, characterized in that, The anti-yellowing agent includes at least one of benzotriazole derivatives and epoxy resin polymers; The wetting agent includes at least one of propylene glycol derivatives; The second solvent includes at least one of ethylene glycol, propylene glycol, and deionized water.

9. A method for three-dimensional printing on fabrics, characterized in that, The method, using the digital inkjet 3D printing ink as described in any one of claims 1-8, comprises: A three-dimensional printed pattern is constructed by printing on a fabric substrate material based on a preset pattern and preset inkjet printing parameters at room temperature. Baking at 140℃-160℃ for 8-10 minutes allows the ink in the three-dimensional pattern to undergo a full chemical cross-linking reaction and solidify.

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