Self-repairable laser thermal sublimation ribbon and preparation method and application thereof

Abstract

The invention belongs to the technical field of thermal sublimation printing, and particularly relates to a self-repairable laser thermal sublimation ribbon and a preparation method and application thereof. The self-repairing laser heat sublimation colored tape comprises a self-repairing dye layer, a photothermal conversion layer and a transparent base material which are arranged in sequence. The self-repairable laser thermal sublimation ribbon provided by the invention can remarkably improve the printing quality, prolong the service life of the ribbon, ensure that the stable performance is kept in multiple printing processes, keep the cost reasonable, meet diversified printing requirements, and is particularly suitable for application scenes with higher requirements on color precision and printing durability.

Description

Technical Field

[0001] The invention belongs to the technical field of thermal sublimation printing, and in particular relates to a self-repairable laser thermal sublimation ribbon and a preparation method and application thereof. Background Art

[0002] Sublimation technology is widely used in photo printing, customized product printing (such as mobile phone cases, cups, etc.), ID photo printing and other fields due to its advantages of continuous color gradation, bright colors and delicate images. As consumers' requirements for printing quality and durability continue to increase, the performance optimization of sublimation ribbons has become a key research direction. Sublimation ribbons are ribbons used in sublimation printing technology. The dye is sublimated by heating and transferred to the substrate to form an image.

[0003] Existing thermal sublimation ribbons have the following limitations: the unevenness and instability of the dye layer will cause color deviation, color blocks, blurring and other problems in the printed pattern, which seriously affects the quality of the printed product and reduces the added value of the product, especially in the field with high color accuracy requirements (such as professional photography printing) cannot meet the needs; the dye transfer rate of the thermal sublimation ribbon is low, and the printed ribbon still remains at least 80% of the original ribbon dye content, resulting in a huge waste of dye and an increase in production costs. Therefore, when the existing thermal sublimation ribbon is used for image printing, there are the following problems: the dye distribution of the dye layer is uneven after one printing, which affects the quality of the next printing; the performance of the dye layer decreases after long-term use or environmental influences, such as dye agglomeration, migration and other phenomena, resulting in a shortened ribbon service life; various factors (such as temperature and pressure changes) may cause incomplete local dye transfer or color deviation during the printing process.

[0004] However, in commercial printing (such as label and ticket printing), existing carbon ribbons may not meet the needs of high-speed printing, and the printed patterns are prone to wear and fade; in personalized customized printing (such as customized gifts and decorative painting printing), it is difficult to achieve high color accuracy and rich color level printing effects; in industrial logo printing, the adhesion and corrosion resistance to substrates of different materials are insufficient.

[0005] At present, there are mainly the following methods to improve the performance of thermal sublimation ribbons:

[0006] 1. Optimize the dye formula and select higher quality and more stable dyes, but the cost is higher and may not solve the problem of long-term stability of the dye layer;

[0007] 2. Improve the ribbon substrate and improve the surface properties of the substrate such as flatness and roughness to improve the coating effect of the dye layer, but the improvement of the internal performance of the dye layer is limited;

[0008] 3. Adjust the printing process parameters, such as print head power, printing speed, etc., but this requires precise equipment control and complex parameter debugging, and has limited adaptability to different ribbons.

[0009] However, the current methods for improving the performance of thermal sublimation ribbons have the following shortcomings:

[0010] 1. Optimizing the dye formula may not fundamentally solve the stability problem of the dye layer during use. For example, the dye may still aggregate and migrate after long-term storage or multiple printings. New high-quality dyes are often more expensive, which will increase product prices and reduce market competitiveness.

[0011] 2. Although improving the substrate may improve the initial coating effect of the dye layer to a certain extent, it cannot solve the problems of the dye layer during the printing process, such as changes in dye distribution caused by heat accumulation; and changes in the substrate may require re-optimization of the entire ribbon production process, increasing technical difficulty and cost;

[0012] 3. Adjusting the printing process parameters can only improve the printing effect within a certain range, but cannot solve the defects of the ribbon material properties. In actual production, the material properties of different batches of ribbons may fluctuate to a certain extent, resulting in the pre-set printing parameters being unable to always maintain the best printing effect, affecting production efficiency and product quality stability. Summary of the invention

[0013] To address the deficiencies of the prior art, the present invention provides a self-repairing laser thermal sublimation ribbon and a preparation method and application thereof. The self-repairing laser thermal sublimation ribbon provided by the present invention can significantly improve the printing quality, extend the service life of the ribbon, ensure stable performance during multiple printing processes, while maintaining reasonable costs, meet diverse printing needs, and is particularly suitable for application scenarios with high requirements for color accuracy and printing durability.

[0014] The technical solution provided by the present invention is as follows:

[0015] A self-repairable laser thermal sublimation ribbon comprises: a self-repairing dye layer, a light-to-heat conversion layer and a transparent substrate which are arranged in sequence.

[0016] Based on the above technical solution:

[0017] During the thermal sublimation printing process, the dye in the area of ​​the self-healing dye layer that has undergone dye transfer can be redistributed evenly under certain conditions, thereby restoring part or all of the printing ability;

[0018] The combined structure of the substrate, the photothermal conversion layer and the self-healing dye layer can ensure the stability of the ribbon during the printing process and good transfer performance, while being compatible with the self-healing function of the self-healing dye layer.

[0019] Substrate

[0020] Material selection and function: Select transparent polyethylene terephthalate film, polypropylene film, polyethylene naphthalate film, polyethylene film, polyvinyl alcohol film or polymethyl methacrylate film with a thickness of 4-10 microns, preferably polyethylene terephthalate (PET) film as the supporting layer, because it has good mechanical strength and can withstand various stresses during the preparation, storage, transportation and use of the carbon ribbon, and is not easy to break or deform; it has high chemical stability and can resist the erosion of ink, solvents and other chemicals, ensuring the stable performance of the carbon ribbon in different chemical environments; it has good dimensional stability and is not easy to expand and contract when the temperature and humidity change, ensuring the transfer accuracy; the surface flatness is high, which is conducive to the uniform coating of the base coat and the ink layer.

[0021] Surface treatment method: The surface of the substrate is treated with corona to make the surface dyne value reach 42-50, which enhances its adhesion with the light-heat conversion layer. The corona treatment time is 5-10 seconds, the power is 1-3kW, and the next coating operation is carried out immediately after the treatment to prevent surface contamination from affecting adhesion.

[0022] Light-to-heat conversion layer

[0023] Material selection and function: It is composed of carbon nanotubes (8%-15% by mass), graphene (3%-8% by mass) and acrylic resin binder (77%-89% by mass). Carbon nanotubes and graphene have excellent light absorption properties, can efficiently absorb laser energy and quickly convert it into heat energy, providing heat for the sublimation of the self-healing dye layer; acrylic resin binder ensures the firm adhesion of the light-to-heat conversion layer on the PET substrate, and has good flexibility and heat resistance.

[0024] Preparation and coating process: Add carbon nanotubes and graphene to an organic solvent (such as N-methylpyrrolidone) containing an appropriate amount of dispersant (such as polyvinyl pyrrolidone, with a mass fraction of 5%-10% of the total mass of carbon nanotubes and graphene), and ultrasonically disperse for 40-60 minutes to form a uniform dispersion. Then dissolve the acrylic resin binder in the above dispersion and stir for 60-90 minutes to obtain a light-to-heat conversion layer coating. Use a micro-gravure coater for coating, the coating speed is 100-200m / min, the drying temperature is 70-90℃, and the coating thickness is controlled at 0.3-0.8μm.

[0025] Self-healing dye layer

[0026] Material composition and function realization: It is composed of sublimation dye (mass fraction 30%-60%), thermoplastic resin (such as polyvinyl pyrrolidone, polyvinyl butyral resin, etc., mass fraction 20%-40%), additives (such as small molecule plasticizers, microcapsules, shape memory materials, thermal responsive solvents, magnetic or electrically responsive materials, etc., mass fraction 10%-30%).

[0027] Sublimation dyes provide the colors required for printing, and thermoplastic resins act as binders to ensure the stability and transferability of the dyes in the ribbon.

[0028] The small molecule plasticizer in the additive (such as adipic acid polyester plasticizer, mass fraction 5%-15%) can reduce the viscosity of the dye when heated, promote the movement of dye molecules, and make the dye redistribute evenly in the coating to achieve self-repair; the wall material structure of the microcapsule (mass fraction 10%-20%, the wall material is a thermal responsive material such as thermoplastic polyurethane or an acrylic polymer with a reversible cross-linking structure, and part of the dye is wrapped inside) changes when heated, and the internal dye can be redistributed; shape memory materials (such as thermal shape memory polyurethane, mass fraction 1%-5%) promote the rearrangement of dye molecules during the process of heat recovery; thermal responsive solvents (such as benzyl alcohol, mass fraction 5%-10%) drive the movement of dye molecules to achieve redistribution when heated and volatilized; magnetic or electrically responsive materials (such as nano ferrite particles or conductive polyaniline, mass fraction 0.5%-2%) drive the directional movement of dye molecules under the action of an external magnetic field or electric field.

[0029] The plasticizer may also be selected from phthalate plasticizers;

[0030] The wall material of the microcapsule may also be selected from polymethyl methacrylate;

[0031] The shape memory material may also be selected from polynorbornene;

[0032] The thermally responsive solvent may also be selected from cyclopentanone.

[0033] Based on the above technical solutions, a repair mechanism based on heat triggering and a repair mechanism driven by electric or magnetic fields can be realized.

[0034] In terms of heat-triggered repair mechanisms:

[0035] Repair under the action of small molecule plasticizers: After the printed ribbon has been printed once, a certain amount of heat is applied to the printed area through an additional heating device (such as an infrared heating plate). The general heating temperature is determined to be between 80-120°C based on the thermal analysis data of the self-repairing dye layer material, and the heating time is 5-15 seconds. At this time, the small molecule plasticizer (such as polyester plasticizer) in the self-repairing dye layer reduces the viscosity of the dye under the action of heat, allowing the dye molecules to move more freely under thermal motion. The dye molecules will diffuse to areas that have become sparse or uneven due to dye transfer, thereby achieving a uniform redistribution of the dye in the entire self-repairing dye layer and achieving the purpose of self-repair.

[0036] Microcapsule repair: Heating changes the thermal responsive structure of the microcapsule wall material. If the microcapsule wall material is thermoplastic polyurethane, the temperature rise will soften it, and the microcapsules may fuse with each other, allowing the dyes encapsulated inside to be exchanged and redistributed between the microcapsules; for acrylic polymer wall materials with reversible cross-linking structures, high temperatures can open the cross-linking bonds, allowing the dyes to be exchanged and redistributed between microcapsules. When the temperature drops, the cross-linking structure can be reformed, thereby achieving the repair of the self-repairing dye layer, restoring the self-repairing dye layer to a relatively uniform state, ready for the next printing.

[0037] Shape memory material repair: Shape memory materials (such as thermal shape memory polyurethane) return to their original state after reaching the transition temperature (generally within the above-mentioned heating temperature range). During this process, physical forces are exerted on the surrounding dyes, driving the dye molecules to move and redistribute, further promoting the self-repair of the self-repairing dye layer.

[0038] Thermal responsive solvent volatilization-diffusion repair: Thermal responsive solvents (such as benzyl alcohol) evaporate when heated, and their vapor diffuses in the self-healing dye layer, driving the dye molecules to move together. As the solvent evaporates and re-condenses, the dye molecules are redistributed under the action of the solvent to achieve self-healing. Moreover, when the temperature is lowered, the remaining solvent can maintain the stability of the self-healing dye layer and prevent the dye from aggregating again.

[0039] For repairs based on electric or magnetic field actuation:

[0040] Magnetic (such as nano-ferrite particles) or electrically responsive materials (such as conductive polyaniline) are added to the ribbon, and an external electric field or magnetic field can be applied as needed after printing. For magnetic particles, a magnetic field of appropriate strength (such as 0.1-1T) can be used; for electrically responsive materials, an electric field generated by an appropriate voltage (such as 10-100V) can be applied. Under the action of the electric field or magnetic field, the magnetic particles or electrically responsive materials will drive the dye molecules to move in a directional manner, causing the dye to be redistributed in the self-healing dye layer, optimizing the self-healing effect, ensuring the uniformity of the self-healing dye layer, and thus improving the quality of the next print.

[0041] Based on the above technical solution:

[0042] The self-repairing dye layer contains a combination of multiple self-repairing additives, which realize the self-repairing of the self-repairing dye layer after printing through different mechanisms, thereby improving the multiple printing performance of the ribbon;

[0043] The synergistic effects of various additives, such as small molecule plasticizers, microcapsules, shape memory materials, special solvents, magnetic or electrically responsive materials, etc., work together to ensure the effective repair of the self-healing dye layer under different conditions.

[0044] Preparation and coating process: Mix sublimation dyes, thermoplastic resins, additives, etc. in a mixing container. Premix for 10-15 minutes using low-speed stirring (300-500rpm), then use a high-speed stirrer to stir at a speed of 1500-2500rpm for 30-60 minutes to fully mix the ingredients. Use gravure coating, with a coating speed of 100-200m / min, a drying temperature of 70-100℃, and a thickness of 0.5-1.5μm according to color requirements (such as 0.8-1.2μm for cyan, 0.6-1.0μm for magenta, and 0.5-0.8μm for yellow).

[0045] The present invention also provides a method for preparing a self-repairable laser thermal sublimation ribbon, comprising the following steps: performing corona treatment on the surface of a substrate, and then sequentially preparing a light-to-heat conversion layer and a self-repairing dye layer.

[0046] The present invention also provides the application of a self-repairable laser thermal sublimation ribbon, which uses ultraviolet light, visible light or infrared light as a laser source for thermal sublimation transfer. The laser thermal sublimation ribbon can be used multiple times, and the number of times of reuse can reach 10 times.

[0047] The beneficial effects of the present invention are as follows:

[0048] 1. Print quality

[0049] Color accuracy is significantly improved, thanks to the stable structure and self-repairing function of the self-repairing dye layer, which makes the color deviation of each print smaller, and the color accuracy is improved by 60%-70% compared with the existing technology, which can meet the professional printing needs with extremely high color accuracy.

[0050] The clarity of the pattern is significantly improved. Since the self-healing dye layer maintains good uniformity during the printing and repair process, the line edges are clearer, the pattern details are better presented, and the clarity is improved by 30%-50% compared with the existing technology.

[0051] 2. Self-repair effect

[0052] Through the synergistic effect of multiple self-repair mechanisms, the ribbon of the present invention can still maintain good dye distribution uniformity and print quality stability after multiple print-repair-print cycles, while traditional ribbons will show obvious quality degradation after several prints and cannot achieve effective self-repair.

[0053] 3. Ribbon stability

[0054] The ribbon of the present invention has excellent performance in both long-term storage stability and chemical stability. After being stored under different environmental conditions and soaked in chemical reagents, it can still maintain good printing performance, while the ribbon of the prior art is prone to performance degradation under similar conditions, such as discoloration, deformation, delamination and serious reduction in printing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 The figure is a schematic structural diagram of the self-repairable laser thermal sublimation ribbon provided by the present invention.

[0056] Figure 2 This is a comparison chart of the effects after printing once and after printing 10 times.

[0057] Attached Figure 1 The structures represented by the labels are listed below:

[0058] 1. Substrate; 2. Photothermal conversion layer; 3. Self-healing dye layer. DETAILED DESCRIPTION

[0059] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0060] Unless otherwise specified, the test methods used in the examples are conventional methods; the materials and reagents used are commercially available reagents and materials unless otherwise specified.

[0061] The preparation method of microcapsules is as follows: first, thermoplastic polyurethane is dissolved in N-methylpyrrolidone (NMP) to prepare a solution with a mass fraction of 12.5%. The sublimation dye is dissolved in an organic solvent (such as ethyl acetate) that is immiscible with TPU to form a dye solution. Under high-speed stirring (4000rpm), the dye solution is slowly added dropwise to the NMP solution of TPU to form an oil-in-water emulsion. Continue stirring for 1.5 hours to stabilize the emulsion. Then, NMP and ethyl acetate are removed by vacuum distillation. As the solvent evaporates, TPU gradually solidifies on the surface of the dye droplets to form microcapsules that encapsulate the dye. Finally, the microcapsules are collected for use through filtering, washing and drying. If the wall material is an acrylic polymer containing a reversible cross-linked structure, first, acrylic monomers (such as methyl methacrylate, butyl acrylate, etc.), crosslinking agents (such as N,N-methylenebisacrylamide), initiators (such as azobisisobutyronitrile) and sublimation dyes are dissolved in an appropriate organic solvent (such as toluene) to prepare a prepolymer solution. Under stirring conditions, the prepolymer solution is slowly added dropwise to an aqueous solution containing an emulsifier (such as sodium dodecyl sulfate) to form an oil-in-water emulsion. The reaction is carried out at a certain temperature (such as 70°C) for 4 hours to allow the acrylic ester monomer to undergo a polymerization and cross-linking reaction to form microcapsules that encapsulate the dye. After the reaction is completed, the microcapsule product is obtained by centrifugation, washing, and drying.

[0062] The preparation method of shape memory material is as follows: first, add polyether diol (such as polytetramethylene glycol) and diisocyanate (such as toluene diisocyanate, TDI) in a certain molar ratio (such as 1:2.5) to a dry reaction vessel, and react at 80°C for 2.5 hours under nitrogen protection to form a prepolymer. Then add a small molecule chain extender (such as 1,4-butanediol) and continue to react for 1.5 hours to obtain a thermal shape memory polyurethane. The reaction temperature, time and ratio of each raw material must be strictly controlled during the reaction to ensure that a product with good shape memory properties is obtained. The synthesized thermal shape memory polyurethane can be processed into the desired shape and size by solution casting or melt extrusion, and then added to the dye layer.

[0063] In a specific embodiment, Figure 1 As shown, the self-repairable laser thermal sublimation ribbon includes a self-repairing dye layer 3, a light-to-heat conversion layer 2 and a transparent substrate 1 which are arranged in sequence.

[0064] Example 1

[0065] PET substrate: Select 8μm PET film and perform corona treatment. The dyne value after treatment is required to be no less than 48.

[0066] Light-to-heat conversion layer

[0067] 10 parts of carbon nanotubes, 5 parts of graphene, 1 part of polyvinyl pyrrolidone dispersant, 50 parts of N-methyl pyrrolidone, after ultrasonic dispersion for 50 minutes, add 84 parts of acrylic resin binder, stir for 75 minutes to obtain the coating. Coating by gravure coater, speed 150m / min, drying at 85℃, thickness 0.5μm.

[0068] Self-healing dye layer

[0069] Sublimation dye (optional brands are CI Disperse Yellow 3, Disperse Red 153, Disperse Blue 3) 40 parts, polyvinyl butyral resin (an optional brand is Sekisui Chemical KS-10) 30 parts, polyester plasticizer (an optional brand is Liancheng UN615) 8 parts, microcapsules (prepared according to the above method, the wall material is thermoplastic polyurethane, and azo sublimation dyes are wrapped inside) 15 parts, thermal shape memory polyurethane 2 parts, benzyl alcohol 6 parts, nano ferrite particles (particle size is 10-50nm) 1 part, after mixing, slit coating at a speed of 120m / min, drying at 90℃, cyan thickness 1.0μm, magenta 0.8μm, yellow 0.6μm.

[0070] Example 2

[0071] PET substrate: same as in Example 1.

[0072] Light-to-heat conversion layer: the same as in Example 1.

[0073] Self-healing dye layer

[0074] Sublimation dye (optional brand models are CI Disperse Yellow 3, Disperse Red 153, Disperse Blue 3) 45 parts, polyvinyl alcohol (an optional brand model is Sekisui Chemical KS-10) 25 parts, polyester plasticizer (an optional brand model is A-8000, manufacturer Hallstar) 10 parts, microcapsules (wall material is an acrylic polymer with a reversible cross-linking structure, and anthraquinone sublimation dye is encapsulated inside) 18 parts, thermal shape memory polyurethane 3 parts, benzyl alcohol 8 parts, conductive polyaniline (an optional brand model is Leyan reagent product number 1065617) 1.5 parts, after mixing, gravure coating, speed 120m / min, drying at 95℃, cyan thickness 1.1μm, magenta 0.9μm, yellow 0.7μm (for color image printing, adjust the formula to optimize color performance).

[0075] Example 3

[0076] Referring to Example 1, the difference is that the adipic acid polyester is replaced by a phthalate plasticizer of dioctyl phthalate (DOP), manufactured by BASF, and the self-repairing performance can still be used 10 times.

[0077] Comparative Example 1

[0078] The carbon ribbon of the prior art is used, specifically without a light-to-heat conversion layer, and is replaced by a primer layer of a PVP system.

[0079] Comparative Example 2

[0080] Refer to Example 1, the difference is that no self-repairing additive is added to the self-repairing dye layer material.

[0081] Comparative Example 3

[0082] Refer to Example 1, the difference is that the self-repairing additive in the self-repairing dye layer material is replaced by sorbitol with better fluidity.

[0083] Performance testing plan

[0084] Use coated paper uniformly

[0085] 1. Print quality test

[0086] Color Accuracy Assessment

[0087] Test equipment and method: Use a color measuring instrument (such as X-Rite i1Pro 2) to measure the color coordinate value (such as Lab* value) of the printed pattern under a standard light source (such as D50 light source), compare it with the standard color value, and calculate the color deviation value (such as ΔE value).

[0088] Quantitative standard: A ΔE value less than 3 is considered to be good color accuracy, and the smaller the ΔE value, the higher the color accuracy.

[0089] Pattern clarity evaluation

[0090] Test equipment and methods: Use a high-resolution optical microscope (magnification 500-1000 times) to observe the line edges of the printed pattern and measure the line width deviation. At the same time, use professional image analysis software (such as ImageJ) to calculate the pattern clarity parameters, such as edge gradient value and modulation transfer function (MTF) value.

[0091] Quantitative standards: line width deviation within ±5%, edge gradient value greater than 50, and MTF value greater than 0.4 at a specific frequency (such as 10lp / mm) are considered to have good clarity.

[0092] 2. Self-repair effect test

[0093] Multiple print-repair-print cycle test: Use the ribbon to perform multiple print-repair-print cycle operations (e.g., 10 cycles). After each print, the printed area is repaired according to the set repair conditions (heating temperature and time, applied electric or magnetic field, etc.). After each repair and before the next print, the surface state of the dye layer is observed through an optical microscope to check the uniformity of the dye distribution.

[0094] About the repair conditions:

[0095] Embodiment 1 is: after one printing, the ribbon is passed through an infrared heating device, the heating temperature is set to 100°C, and the heating time is 8 seconds. The magnetic field can be used to assist in repair. While heating, a 0.3T magnetic field is applied, and the direction of the magnetic field is perpendicular to the plane of the ribbon. After heating and magnetic field action, the ribbon is cooled, and the cooling method is to cool naturally to room temperature, so that the ribbon is restored to a state that can be printed again.

[0096] Example 2 is: After printing is completed, the ribbon is heated and repaired in a hot air circulation oven. The oven temperature is set to 110°C, and the ribbon stays in the oven for 12 seconds. Since the ribbon in this embodiment is added with an electrically responsive material such as conductive polyaniline, electric field-assisted repair is performed by applying a 40V DC voltage to both ends of the ribbon while heating, and the electric field is applied for 10 seconds. After the heating and electric field treatment is completed, the ribbon is placed in a well-ventilated environment and quickly cooled to about 30°C in preparation for the next printing. Such repair conditions help to change the structure of the microcapsule wall material and allow small molecule plasticizers to play a role. At the same time, under the action of the electric field, the conductive polyaniline drives the dye molecules to redistribute, thereby achieving effective repair of the dye layer.

[0097] Comparative Examples 1 and 2 have no self-repairing ability.

[0098] Comparative Example 3 is the same as Example 1.

[0099] Quantitative evaluation indicators: calculate the change in uniformity of dye distribution after each cycle (such as calculating the standard deviation of dye concentration distribution through image analysis software, the smaller the standard deviation, the higher the uniformity), and observe the changes in the quality of the printed pattern (color accuracy and clarity). If the uniformity of the dye layer remains good (small standard deviation fluctuation range) and the printing quality is stable (color deviation and clarity index fluctuations are within the allowable range) after multiple cycles, it indicates that the self-healing effect is good.

[0100] 3. Ribbon stability test

[0101] Long-term storage stability test

[0102] Test method: Place the ribbon samples under different environmental conditions (such as high temperature and high humidity: temperature 60°C, relative humidity 90%; low temperature and low humidity: temperature -20°C, relative humidity 20%) and store them for a certain period of time (such as 1, 3, 6 months).

[0103] Performance test: Then, the ribbon is tested for printing quality (color accuracy, pattern clarity) and self-repair function (as described above). If there is no significant change in printing quality and self-repair function under different storage conditions and time, it indicates that the ribbon has good stability during long-term storage.

[0104] Test Results

[0105]

[0106] like Figure 2 As shown, it is a comparison chart of the effect after printing once and 10 times with the carbon ribbon of Example 1, wherein the left side is after printing once, and the right side is after printing 10 times. It can be seen that based on the repair function, the color expression is still good after printing 10 times.

[0107] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A self-repairable laser thermal sublimation ribbon, characterized in that: The invention comprises: a self-repairing dye layer, a light-to-heat conversion layer and a transparent substrate which are arranged in sequence.

2. The self-repairable laser thermal sublimation ribbon according to claim 1, characterized in that: The light-to-heat conversion layer comprises the following components in mass percentage: 8%-15% carbon nanotubes, 3%-8% graphene, and 77%-89% acrylic resin binder; the thickness of the light-to-heat conversion layer is 0.3-0.8 μm.

3. The self-repairable laser thermal sublimation ribbon according to claim 1, characterized in that: The self-repairing dye layer comprises the following components in mass percentage: 30%-60% of sublimation dye, 20%-40% of thermoplastic resin, and 10%-30% of self-repairing additive; the thickness of the self-repairing dye layer is 0.5-1.5 μm.

4. The self-repairable laser thermal sublimation ribbon according to claim 3, characterized in that: The self-repairing additive is selected from any one or more of a plasticizer, a microcapsule, a shape memory material, a thermally responsive solvent, a magnetically responsive material or an electrically responsive material.

5. The self-repairable laser thermal sublimation ribbon according to claim 4, characterized in that: The plasticizer is selected from adipic acid polyester plasticizer or phthalate plasticizer; the mass percentage of the plasticizer is 5%-15%; The wall material of the microcapsule is thermoplastic polyurethane, acrylic polymer containing a reversible cross-linking structure or polymethyl methacrylate, the core material of the microcapsule is dye; and the mass percentage of the microcapsule is 10%-20%.

6. The self-repairable laser thermal sublimation ribbon according to claim 4, characterized in that: The shape memory material is selected from thermo-induced shape memory polyurethane or polynorbornene; the mass percentage of the shape memory material is 1%-5%; The thermal response solvent is selected from benzyl alcohol or cyclopentanone; the mass percentage of the thermal response solvent is 5%-10%.

7. The self-repairable laser thermal sublimation ribbon according to claim 4, characterized in that: The magnetic responsive material is selected from nano ferrite particles; the mass percentage of the magnetic responsive material is 0.5%-2%; The electrically responsive material is selected from conductive polyaniline; the mass percentage of the electrically responsive material is 0.5%-2%.

8. The self-repairable laser thermal sublimation ribbon according to claim 1, characterized in that: The substrate is selected from transparent polyethylene terephthalate film, polypropylene film, polyethylene naphthalate film, polyethylene film, polyvinyl alcohol film or polymethyl methacrylate film; the thickness of the substrate is 4-10 μm.

9. A method for preparing a self-repairable laser thermal sublimation ribbon according to any one of claims 1 to 8, characterized in that: The following steps are involved: The surface of the substrate is subjected to corona treatment, and then a light-to-heat conversion layer and a self-healing dye layer are prepared in sequence.

10. An application of the self-repairable laser thermal sublimation ribbon according to any one of claims 1 to 8, characterized in that: Ultraviolet light, visible light or infrared light is used as the laser source for thermal sublimation transfer.

Images