Novel gold stamping thermal transfer ribbon and preparation method thereof

Abstract

The invention relates to the technical field of heat transfer printing, in particular to a novel gold stamping thermal transfer ribbon and a preparation method thereof. The novel gold stamping thermal transfer ribbon comprises a base material, a pigment layer, a release film release layer and an aluminum plating layer, the base material is a biaxially oriented polyethylene glycol terephthalate film, the thickness of the base material is 4-5 microns, and the thickness of the release film release layer is 0.1-0.5 microns. The base material can effectively improve the heat conduction efficiency and ensure that the transfer printing temperature is uniform, so that the transfer printing speed and the transfer printing precision are improved; the release layer and the demolding layer are integrated into a single composite layer with low thickness, so that the production process is simplified, and the material cost is reduced; according to the preparation method, high-density, uniform and extremely-thin metal deposition can be completed in one step through vacuum evaporation, and the gold stamping transfer printing thermal transfer ribbon can achieve the multi-color superposition effect.

Description

Technical Field

[0001] This invention relates to the field of heat transfer technology, and more specifically, to a novel hot stamping ribbon and its preparation method. Background Technology

[0002] Hot stamping, as an important surface decoration process, is widely used in packaging, printing, and other fields. Its core material, hot stamping ribbon, achieves pattern transfer through heat transfer. In existing technologies, hot stamping ribbon typically consists of multiple layers, including a substrate, a release layer, a functional layer (pigment / metal layer), and an adhesive layer. A typical structure uses PET film as the substrate, with a thickness of approximately 12-25 μm. The release layer is set separately, and the material is mostly paraffin wax or oxidized polyethylene wax, serving only as a release agent. The functional layer contains pigments and a vacuum-deposited aluminum layer, providing color and metallic texture. The adhesive layer is used to bond the transfer layer to the substrate. Some products have an additional back coating to improve heat resistance.

[0003] Although this type of carbon ribbon completes basic hot stamping, the separate design of the release layer and the stripping layer makes its function limited. After the transfer, the surface water contact angle is greater than 60°, and the surface is prone to dirt accumulation and difficult to clean. It has no self-cleaning ability and requires manual maintenance. The traditional separate design of the release layer and the stripping layer leads to limited function. At the same time, the surface tension is low after the transfer, making it impossible to print a second coating and making it difficult to achieve multi-color effects. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a novel hot stamping carbon ribbon and its preparation method.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: This invention provides a novel hot stamping ribbon, characterized in that it includes a substrate, on which a pigment layer, a release liner layer and an aluminum plating layer are sequentially disposed; the substrate is a biaxially oriented polyethylene terephthalate film with a thickness of 4-5 μm, and the release liner layer has a thickness of 0.1-0.5 μm.

[0006] Based on the above technical solution, the present invention can be further improved as follows.

[0007] Furthermore, the thickness of the pigment layer is 0.3-0.7 μm.

[0008] Furthermore, an adhesive layer and a back coating layer are sequentially disposed on the aluminum plating layer. The thickness of the aluminum plating layer is 30-50 nm, the thickness of the adhesive layer is 0.1-0.3 μm, and the thickness of the back coating layer is 0.3-0.7 μm.

[0009] Furthermore, the material of the release liner includes tetramethoxysilane oligomers.

[0010] Furthermore, the release liner material also includes carnauba wax, with the carnauba wax comprising 70-80 parts by mass and the tetramethoxysilane oligomer comprising 20-30 parts by mass.

[0011] The present invention also provides a method for preparing a novel hot stamping ribbon as described above, wherein the release liner and the pigment layer are prepared sequentially on the substrate, and the aluminum plating layer is prepared by vacuum evaporation.

[0012] Furthermore, the evaporation temperature is 1200-1500℃, and the vacuum degree is 10. -3 -10 -4 Pa.

[0013] Furthermore, the release liner is prepared by mixing carnauba wax, tetramethoxysilane oligomer and organic solvent in a certain proportion and applying the mixture onto the substrate at a speed of 100-150 m / min.

[0014] Furthermore, the method also includes the step of sequentially preparing an adhesive layer and a back coating layer on the aluminum plating layer.

[0015] The present invention also provides a multi-color hot stamping transfer method, comprising the following steps: printing the novel hot stamping ribbon as described above onto a re-transfer film with an image to obtain a hot stamping ribbon coating; printing a white adhesive ribbon onto the hot stamping ribbon coating, and then transferring it onto the target paper to complete the multi-color hot stamping transfer.

[0016] The beneficial effects of this invention are as follows: (1) The novel hot stamping ribbon of the present invention has a BOPET film as the substrate and adopts a thin design, which can effectively improve the heat conduction efficiency and ensure uniform transfer temperature, thereby improving the transfer speed and transfer accuracy. (2) The novel hot stamping carbon ribbon of the present invention integrates the release layer and the release film layer into a single composite layer with a thickness of only 0.1-0.5μm, which simplifies the production process and reduces material costs; (3) The novel hot stamping ribbon of the present invention introduces silanol groups into the release liner material to make the surface after transfer hydrophilic, realizes the self-cleaning function of dirt automatically detaching with water, and supports secondary printing due to the increase in surface tension, and finally achieves the hot stamping effect of multiple colors superimposed. (4) The method for preparing the novel hot stamping carbon ribbon of the present invention can complete the high density, uniformity and extremely thin metal deposition in one step by vacuum evaporation. It can closely cooperate with the pigment layer below to improve the mirror gloss and color saturation, while maintaining the overall thermal resistance at extremely low level, so that the transfer temperature can be transferred quickly and evenly, achieving fine pattern transfer and reducing energy consumption. (5) The multi-color hot stamping transfer method of the present invention includes pretreatment of the transfer film and two-time transfer of multi-color hot stamping process to achieve a multi-color superposition effect. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the layer structure of the novel hot stamping carbon ribbon of the present invention.

[0018] The attached diagram lists the components represented by each number as follows: 1. Substrate; 2. Release film layer; 3. Pigment layer; 4. Aluminum plating layer; 5. Adhesive layer; 6. Back coating layer. Detailed Implementation

[0019] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0020] like Figure 1 As shown, the novel hot stamping ribbon of the present invention includes a substrate 1, on which a pigment layer 3, a release liner 2 and an aluminum plating layer 4 are sequentially disposed; the substrate 1 is a biaxially oriented polyethylene terephthalate film (BOPET) with a thickness of 4-5 μm, and the release liner 2 has a thickness of 0.1-0.5 μm.

[0021] The novel hot stamping ribbon of this invention has a substrate 1 of BOPET film, which has a temperature resistance greater than 180°C and also has good mechanical strength and dimensional stability. Its thin design of 4-5μm can effectively improve heat conduction efficiency and ensure uniform transfer temperature, thereby improving transfer speed and transfer accuracy. At the same time, the release layer and the stripping layer are integrated into a single composite layer with a thickness of only 0.1-0.5μm, which simplifies the production process and reduces material costs.

[0022] Preferably, the material of the release layer 2 includes tetramethoxysilane oligomers; by introducing silanol groups, the surface after transfer becomes hydrophilic, realizing the self-cleaning function of dirt automatically detaching with water, and supporting secondary printing due to the increased surface tension, ultimately achieving a multi-color overlay hot stamping effect.

[0023] The self-cleaning function refers to the property that dirt can be automatically removed by water flow after the hot stamping ribbon transfers due to the increased hydrophilicity (reduced water contact angle) of the surface.

[0024] Preferably, the release layer 2 also includes carnauba wax, with 70-80 parts by weight of carnauba wax and 20-30 parts by weight of tetramethoxysilane oligomer. The release layer 2 is formed by blending 70-80 parts by weight of carnauba wax with 20-30 parts by weight of tetramethoxysilane oligomer. This not only ensures smooth and instantaneous removal of the hot stamping by relying on the low peeling force of carnauba wax, but also reduces the surface water contact angle to below 30° by using the silanol groups generated by the hydrolysis of tetramethoxysilane. This gives the surface after transfer both self-cleaning ability and high surface tension, thereby simplifying the production process and directly supporting the firm adhesion of subsequent multi-color coatings.

[0025] Preferably, the thickness of the pigment layer 3 is 0.3-0.7μm; this thickness can provide full and uniform color and metallic texture after transfer, while avoiding the increase in transfer energy requirements and blurring of pattern edges caused by excessive thickness. At the same time, it ensures that it works in conjunction with the 30-50nm aluminum plating layer 4 to form a high-gloss decorative effect and maintain the overall heat conduction efficiency.

[0026] Preferably, the material of pigment layer 3 includes 50-60 parts by weight of thermoplastic acrylic resin, 10-15 parts by weight of nano-sized pigment, and 1-2 parts by weight of light stabilizer; more preferably, the light stabilizer is Tinuvin 460.

[0027] Preferably, an adhesive layer 5 and a back coating layer 6 are sequentially disposed on the aluminum plating layer 4. The thickness of the aluminum plating layer 4 is 30-50 nm, the thickness of the adhesive layer 5 is 0.1-0.3 μm, and the thickness of the back coating layer 6 is 0.3-0.7 μm. The 30-50 nm aluminum plating layer 4 enhances the decorative brightness while ensuring high metallic luster and low thermal resistance. The 0.1-0.3 μm adhesive layer 5 forms a strong bond and saves materials under low temperature and rapid transfer conditions. The 0.3-0.7 μm back coating layer 6 provides heat resistance and wear resistance protection simultaneously during high temperature processes. The synergistic thickness of the three layers optimizes the overall heat conduction efficiency, transfer firmness, and service life.

[0028] Preferably, the material of the adhesive layer 5 includes 60-70 parts by weight of carboxyl-type chloroacetic acid resin, 20-30 parts by weight of chlorinated polypropylene, and 1-3 parts by weight of curing agent. More preferably, the curing agent is HDI trimer.

[0029] Preferably, the material of the back coating 6 includes 70-80 parts by weight of silicone-modified resin and 5-10 parts by weight of wear-resistant agent.

[0030] Preferably, the wear-resistant agent is talc powder with a particle size of 10,000-20,000 mesh.

[0031] The method for preparing the novel hot stamping ribbon of the present invention involves sequentially preparing a release layer 2 and a pigment layer 3 on a substrate 1, and then preparing an aluminum plating layer 4 by vacuum evaporation.

[0032] The above-mentioned preparation method of the present invention can complete the deposition of highly dense, uniform and extremely thin metal in one step through vacuum evaporation. It can closely cooperate with the pigment layer 3 below to improve the mirror gloss and color saturation, while maintaining extremely low overall thermal resistance, so that the transfer temperature can be transferred quickly and evenly, achieving fine pattern transfer and reducing energy consumption.

[0033] Evaporation deposition is a technique that involves heating a metal to its evaporation or sublimation temperature in a vacuum environment, causing its atoms or molecules to escape and deposit as a continuous thin film on the surface of a substrate.

[0034] Preferably, the evaporation temperature is 1200-1500℃ and the vacuum degree is 10. -3 -10 -4 Pa; allows aluminum atoms to evaporate fully and be deposited in a directional manner, forming a dense and uniform aluminum plating layer of 30-50nm4, which not only enhances the metallic luster and reflectivity but also maintains low thermal resistance, ensuring efficient heat transfer and complete pattern transfer during the transfer process, while avoiding oxidation and improving the interlayer bonding strength.

[0035] Preferably, the release liner 2 is prepared by mixing carnauba wax, tetramethoxysilane oligomer and organic solvent in a certain proportion and coating it onto the substrate 1 at a speed of 100-150 m / min.

[0036] Carnauba wax, tetramethoxysilane oligomer, and organic solvent are mixed evenly in a certain proportion and coated onto the substrate at a high speed of 100-150 m / min. This allows the release layer 2 to form a film with uniform thickness and a smooth surface in a very short time. This ensures that the wax phase spreads quickly and provides low peel force, while also allowing the silane component to fully hydrolyze to generate hydrophilic groups. This simultaneously achieves smooth release and self-cleaning functions. At the same time, the high-speed process shortens the cycle time, reduces energy consumption, and increases production capacity.

[0037] Preferably, the method further includes the step of sequentially preparing an adhesive layer 5 and a back coating layer 6 on the aluminum plating layer 4.

[0038] In one embodiment of the present invention, the specific steps of the preparation method are as follows: (1) Preparation of release layer 2: Mix 70-80 parts by weight of carnauba wax, 20-30 parts by weight of tetramethoxysilane oligomer with a solvent, the solvent being a mixture of 2-butanone and toluene in a mass ratio of 1:1.

[0039] The material of the above-mentioned mixed release layer 2 is coated onto the front side of the substrate 1 using a gravure coating machine.

[0040] After coating, the silicate in the tetramethoxysilane oligomer decomposes in water to generate silanol groups (-Si-OH), reducing the surface water contact angle to below 30°, allowing dirt to be washed away with rainwater; at the same time, carnauba wax ensures smooth peeling during transfer, achieving the integration of release and demolding functions.

[0041] (2) Preparation of pigment layer 3: Mix 50-60 parts by weight of thermoplastic acrylic resin, 10-15 parts by weight of nano-sized pigment, 1-2 parts by weight of light stabilizer, and 20-30 parts by weight of solvent.

[0042] The color of the nanoscale pigment can be gold or ethereal.

[0043] The light stabilizer can be Tinuvin 460.

[0044] The solvent used in this step is the same as in step (2), which is a mixture of 2-butanone and toluene in a mass ratio of 1:1.

[0045] The above-mentioned mixed material is coated onto the release liner 2 using a gravure coating machine. The coating thickness is 0.3-0.7μm, which can provide basic color and protect the aluminum plating layer 4.

[0046] (3) Preparation of aluminum plating layer 4: The aluminum wire is evaporated and deposited on the surface of pigment layer 4 by vacuum evaporation process.

[0047] (4) Preparation of adhesive layer 5: Mix 60-70 parts by weight of carboxyl-type chloroacetic acid resin, 20-30 parts by weight of chlorinated polypropylene, 1-3 parts by weight of curing agent, and 10-20 parts by weight of solvent.

[0048] Preferably, the curing agent is HDI trimer; the solvent in this step is the same as in step (2), which is a mixture of 2-butanone and toluene with a mass ratio of 1:1.

[0049] The above-mentioned mixed material is coated onto the aluminum layer 4 using a microgravure coating machine.

[0050] (5) Preparation of back coating 6: Mix 70-80 parts by weight of silicone-modified resin, 5-10 parts by weight of wear-resistant agent, and 10-20 parts by weight of solvent.

[0051] The multi-color hot stamping transfer method of the present invention includes the following steps: printing the above-mentioned novel hot stamping ribbon onto a re-transfer film with an image to obtain a hot stamping ribbon coating; printing a white adhesive ribbon onto the hot stamping ribbon coating, and then transferring it onto the target paper to complete the multi-color hot stamping transfer.

[0052] The multi-color hot stamping transfer method of the present invention first transfers the metallic pattern onto the re-transfer film of the printed color image using a novel hot stamping ribbon, and then transfers the composite layer as a whole onto the target paper using a white adhesive ribbon. This achieves high-precision superposition of metallic luster and arbitrary color patterns, breaking through the limitations of traditional monochrome hot stamping. At the same time, the white adhesive layer enhances color saturation and paper adhesion by utilizing its covering and bonding effects, ensuring that the final product presents a bright, firm and richly layered multi-color hot stamping effect.

[0053] Among them, the white bonding ribbon is a universal bonding ribbon that can transfer hot stamping coatings to different paper surfaces.

[0054] The present invention will be illustrated by specific embodiments below.

[0055] Example 1 In this embodiment, substrate 1 is a 4.5μm BOPET film (Guangdong Shunming).

[0056] The material composition of the release layer 2 is: 75 parts carnauba wax, 25 parts tetramethoxysilane oligomer, 40 parts 2-butanone, and 40 parts toluene, with a coating thickness of 0.3 μm.

[0057] The material composition of pigment layer 3 is as follows: 55 parts acrylic resin, 12 parts gold pigment, 1.5 parts Tinuvin 460, 15 parts 2-butanone, and 16.5 parts toluene, with a coating thickness of 0.5 μm.

[0058] The material composition of aluminum plating layer 4 is: vapor-deposited aluminum layer with a thickness of 40nm.

[0059] The material composition of adhesive layer 5 is: 65 parts of chlorinated vinyl resin, 25 parts of chlorinated polypropylene, 2 parts of HDI curing agent, and 8 parts of solvent, with a coating thickness of 0.2 μm.

[0060] The material composition of the back coating 6 is: 75 parts of silicone modified resin, 8 parts of wear-resistant agent, and 17 parts of solvent, with a coating thickness of 0.5 μm.

[0061] Example 2 In this embodiment, the thickness of the release liner 2 is adjusted to 0.5 μm, the thickness of the pigment layer 3 is 0.7 μm, and other parameters are the same as in Embodiment 1.

[0062] Comparative Example 1 The substrate 1 in this comparative example has a thickness of 8 mm, and other parameters are the same as in Example 1.

[0063] Comparative Example 2 This comparative example uses a conventional carbon ribbon structure with independently set release layers and demolding layers. The release layer consists of 90 parts solvent, 9 parts carnauba wax, and 1 part EVA, while the other layers are the same as in Example 1.

[0064] The carbon ribbons obtained in the above embodiments and comparative examples were subjected to performance tests, and the specific test methods are as follows: (1) Self-cleaning test: Contact angle measurement: Use a contact angle meter to measure the water contact angle on the surface after transfer; <30° is acceptable. Dirt removal test: The surface is coated with simulated dirt (a mixture of toner and engine oil), and 20°C clean water (flow rate 50mL / min) is sprayed on it. The dirt residue rate is observed. <5% is considered qualified.

[0065] Surface tension test: The surface tension after transfer is measured using the pendant drop method. A value >35mN / m is considered acceptable.

[0066] (2) Adhesion test: Refer to ISO 2409 cross-cut test to test the adhesion between the transfer layer and the re-transfer film, and between the white adhesive ribbon and the transfer layer. Grade 0-1 is qualified.

[0067] (3) Evaluation of color effect: Visually evaluate the color saturation and clarity of the pattern. No smudging or layering is considered qualified.

[0068] The test results are shown in Table 1: Table 1 In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0069] 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 invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0070] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0071] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0072] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. 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. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0073] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A novel hot stamping carbon ribbon, characterized in that, The substrate (1) includes a pigment layer (3), a release film layer (2) and an aluminum plating layer (4) sequentially disposed on the substrate (1); the substrate (1) is a biaxially oriented polyethylene terephthalate film with a thickness of 4-5 μm, and the release film layer (2) has a thickness of 0.1-0.5 μm.

2. The novel hot stamping carbon ribbon according to claim 1, characterized in that, The thickness of the pigment layer (3) is 0.3-0.7 μm.

3. The novel hot stamping carbon ribbon according to claim 2, characterized in that, An adhesive layer (5) and a back coating layer (6) are sequentially disposed on the aluminum plating layer (4). The thickness of the aluminum plating layer (4) is 30-50 nm, the thickness of the adhesive layer (5) is 0.1-0.3 μm, and the thickness of the back coating layer (6) is 0.3-0.7 μm.

4. A novel hot stamping carbon ribbon according to any one of claims 1-3, characterized in that, The material of the release layer (2) includes tetramethoxysilane oligomers.

5. A novel hot stamping carbon ribbon according to claim 4, characterized in that, The release layer (2) also includes carnauba wax, which is 70-80 parts by mass and the tetramethoxysilane oligomer is 20-30 parts by mass.

6. A method for preparing a novel hot stamping carbon ribbon as described in any one of claims 1-5, characterized in that, The release film layer (2) and the pigment layer (3) are sequentially prepared on the substrate (1), and the aluminum plating layer (4) is prepared by vacuum evaporation.

7. The method for preparing a novel hot stamping carbon ribbon according to claim 6, characterized in that, The evaporation temperature is 1200-1500℃, and the vacuum degree is 10. -3 -10 -4 Pa.

8. The method for preparing a novel hot stamping carbon ribbon according to claim 6, characterized in that, The release film layer (2) is prepared by mixing carnauba wax, tetramethoxysilane oligomer and organic solvent in a certain proportion and coating it onto the substrate (1) at a speed of 100-150 m / min.

9. The method for preparing a novel hot stamping carbon ribbon according to claim 6, characterized in that, It also includes the step of sequentially preparing an adhesive layer (5) and a back coating layer (6) on the aluminum plating layer (4).

10. A method for multi-color hot stamping transfer, characterized in that, Includes the following steps: The novel hot stamping ribbon as described in any one of claims 1-5 is printed onto a retransfer film with an image to obtain a hot stamping ribbon coating. The white adhesive ribbon is printed onto the hot stamping ribbon coating and then transferred onto the target paper to complete the multi-color hot stamping transfer.

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