A vacuum electroplated laser DTF white ink hot stamping film and its preparation method

Abstract

This invention discloses a vacuum electroplated laser DTF white ink heat transfer film and its preparation method, relating to the field of heat transfer materials. The vacuum electroplated laser DTF white ink heat transfer film comprises a base film layer, a release layer, a laser molding layer, an aluminum plating layer, and an ink-absorbing coating layer arranged sequentially. The ink-absorbing coating is made from an ink-absorbing paint, which includes hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane, aminosilane coupling agent-modified nano-silica, a blocked isocyanate curing agent, polyether-grafted modified PVA, and other basic additives. In this application, through the synergistic effect of the components, a vacuum electroplated laser DTF white ink heat transfer film with clear and complete patterns, distinct boundaries, excellent heat resistance, and superior resistance to low-temperature cracking can be obtained.

Description

Technical Field

[0001] This application relates to the field of hot stamping materials, and in particular to a vacuum electroplated laser DTF white ink hot stamping film and its preparation method. Background Technology

[0002] Hot stamping technology, with its advantages of giving products exquisite patterns and increasing their added value, has been widely used in printing and packaging, textile printing and dyeing and other fields. Among them, vacuum electroplated DTF white ink hot stamping film is an important hot stamping material, and its performance directly affects the hot stamping effect.

[0003] Currently, in related technologies, vacuum electroplated DTF white ink heat transfer films are prone to problems such as unclear pattern printing, poor low-temperature toughness, and poor heat resistance. These properties of the heat-transfer pattern are closely related to the performance of the ink-absorbing coating. However, existing ink-absorbing coatings typically struggle to improve the heat resistance and low-temperature crack resistance of the printed pattern while simultaneously achieving clear, complete, and well-defined boundaries. Therefore, developing a vacuum electroplated laser DTF white ink heat transfer film that can balance pattern clarity, heat resistance, and low-temperature crack resistance is of significant research importance. Summary of the Invention

[0004] In order to obtain a vacuum electroplated laser DTF white ink hot stamping film with clear and complete patterns, distinct boundaries, excellent heat resistance and low-temperature crack resistance, this application provides a vacuum electroplated laser DTF white ink hot stamping film and its preparation method.

[0005] In the first aspect, the vacuum electroplated laser DTF white ink hot stamping film provided in this application adopts the following technical solution: a vacuum electroplated laser DTF white ink hot stamping film, comprising a base film layer, a release layer, a laser molding layer, an aluminum plating layer and an ink-absorbing coating layer arranged sequentially.

[0006] The ink-absorbing coating is made from an ink-absorbing paint, which includes hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane, aminosilane coupling agent-modified nano-silica, blocked isocyanate curing agent, polyether graft-modified PVA, and other basic additives.

[0007] The hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is prepared from polytetrahydrofuran ether glycol, polyethylene glycol, polypropylene glycol, hydroxyethyl-terminated polydimethylsiloxane, diisocyanate, 2,2-dimethylolpropionic acid, neutralizing agent, catalyst, acetone and water in a weight ratio of (33-38), (12-16): (8.5-9.8): (5.8-6.5): (12.8-14.2): (1-2): (0.8-1.2): (0.05-0.08): (10-15): (25-30).

[0008] The polyether-grafted modified PVA is obtained by alcoholysis of modified polyvinyl acetate, alkenyl polyether, emulsifier, initiator, chain transfer agent, pH adjuster and water in a weight ratio of (65-75):(25-35):(3-4):(4-5):(0.1-0.3):(0.2-0.3):100.

[0009] In this application, hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane and polyether-grafted modified PVA are used as the main film-forming materials and binders for the ink-absorbing coating. Combined with aminosilane coupling agent-modified nano-silica and basic additives, they provide a uniform, tough, and heat-resistant porous coating, which improves the printing uniformity, clarity, and integrity of the ink, resulting in a vacuum electroplating laser DTF white ink heat transfer film with clear and complete patterns, excellent heat resistance, and superior resistance to low-temperature cracking. The blocked isocyanate curing agent, used as the curing agent for the ink-absorbing coating, can react and crosslink with the hydroxyl groups in the hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane and polyether-grafted modified PVA after being deblocked by heating, which helps improve heat resistance. To prevent damage to the base film layer, the deblocking temperature of the blocked isocyanate curing agent is controlled at 80-90℃.

[0010] Compared to waterborne polyurethane without hydroxyethyl-terminated polydimethylsiloxane, adding an appropriate amount of hydroxyethyl-terminated polydimethylsiloxane improves the thermal stability of the ink-absorbing coating while maintaining flexibility. However, the amount of hydroxyethyl-terminated polydimethylsiloxane added should not be excessive, as excessive addition can reduce the ink absorption performance of the coating, leading to unclear printing or uneven color distribution.

[0011] In addition, the amount of alkenyl polyether incorporated into polyether-grafted modified PVA should not be too much. Too much can also affect the ink absorption performance of the ink-absorbing coating, making it difficult to quickly fix the ink and easily causing problems such as unclear printing or uneven color distribution.

[0012] In some specific embodiments, the ink-absorbing coating is prepared from 40-50 wt% hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane, 10-15 wt% aminosilane coupling agent-modified nano-silica, 6.8-8.2 wt% blocked isocyanate curing agent, 0.1-1.0 wt% wetting agent, 0.1-0.8 wt% defoamer, 0.1-0.5 wt% leveling agent, 0.5-2.0 wt% dispersant, and the balance being 10-15% polyether-grafted modified PVA aqueous solution.

[0013] In this application, the weight ratio of each component in the ink-absorbing coating is controlled within the above-mentioned range, which is beneficial to the uniform dispersion of each raw material and the stability of the product. At the same time, by combining the components in a specific ratio, it is beneficial to obtain an ink-absorbing coating that takes into account both excellent heat resistance and toughness, without affecting the ink absorption and ink fixation capabilities of the ink-absorbing coating, and thus obtaining clear, complete, and well-defined printed patterns.

[0014] In some specific embodiments, the number average molecular weights of the polytetrahydrofuran ether diol, polyethylene glycol, and polypropylene glycol are all in the range of 1500-2500.

[0015] In some specific embodiments, the viscosity of the hydroxyethyl-terminated polydimethylsiloxane is 340-380 mPa·s.

[0016] In some specific embodiments, the preparation method of the hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is as follows:

[0017] Polytetrahydrofuran ether glycol, polyethylene glycol, polypropylene glycol, hydroxyethyl-terminated polydimethylsiloxane, and 2,2-dimethylolpropionic acid were dissolved at 50-55℃, dehydrated under vacuum, and then cooled to 75-80℃. Diisocyanate and catalyst were added and reacted for 2.5-3 hours. The mixture was then cooled to 45℃, acetone and a neutralizing agent were added, and water was added while stirring. Finally, acetone was recovered by distillation to obtain hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane.

[0018] In some specific embodiments, the alkenyl polyether is an allyl epoxy-terminated polyoxyethylene polyoxypropylene ether, wherein the degree of polymerization of the polyoxyethylene segment is 20-25 and the degree of polymerization of the polyoxypropylene segment is 10-15.

[0019] In this application, the alkenyl polyether is preferably allyl epoxy-terminated polyoxyethylene polyoxypropylene ether, and the degree of polymerization of the polyoxyethylene segment is controlled to be 20-25 and the degree of polymerization of the polyoxypropylene segment to be 10-15. This improves the compatibility between the polyether-grafted modified PVA and the hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane, while providing excellent toughness without affecting the ink absorption and ink retention capabilities of the ink-absorbing coating, resulting in clear, complete, and well-defined printed patterns. Furthermore, the epoxy groups on the allyl epoxy-terminated polyoxyethylene polyoxypropylene ether can react and bond with the amino groups on the aminosilane coupling agent-modified nano-silica, improving the interfacial toughness between organic and inorganic materials.

[0020] In some specific embodiments, the emulsifier comprises sodium dodecyl sulfate and OP-10, wherein the weight ratio of sodium dodecyl sulfate to OP-10 is 1:(1-1.5).

[0021] In some specific embodiments, the initiator is a persulfate aqueous solution with a mass concentration of 25-35%.

[0022] In some specific embodiments, the preparation method of the polyether grafted modified PVA includes the following steps: dissolving an emulsifier in water accounting for 70-80% of the total weight of water, then adding vinyl acetate and alkenyl polyether, and forming a pre-emulsion at a shear rate of 1000-2000 r / min;

[0023] Dissolve the pH adjuster in the remaining water until homogeneous, then add 10-15% of the pre-emulsion by weight and 30-35% of the initiator by weight to obtain the seed emulsion.

[0024] The remaining pre-emulsion and initiator were added dropwise to the seed emulsion simultaneously, and the reaction temperature was controlled at 75-80℃. After the addition was completed, the temperature was raised to 85-90℃ and kept at that temperature for 1-1.5 hours. Then, the mixture was cooled, filtered to remove impurities, and the modified polyvinyl acetate emulsion was obtained. After the modified polyvinyl acetate emulsion was demulsified, it was centrifuged to obtain the modified polyvinyl acetate.

[0025] Modified polyvinyl acetate was subjected to alcoholysis to obtain polyether-grafted modified PVA.

[0026] In some specific embodiments, the alcoholysis step is carried out in a solution with a methanol mass concentration of 15-20% and a sodium hydroxide mass concentration of 0.2-0.5%.

[0027] Secondly, the preparation method of the vacuum electroplating laser DTF white ink hot stamping film provided in this application adopts the following technical solution:

[0028] A method for preparing a vacuum electroplated laser DTF white ink hot stamping film includes the following steps:

[0029] A release agent is applied to the surface of the base film layer to form a release layer;

[0030] Laser molding material is coated on the side of the release layer away from the base film layer, and after curing, a laser molding layer is formed.

[0031] Aluminum is vapor-deposited on the side of the laser-molded layer that is away from the release layer to form an aluminum-plated layer;

[0032] Apply ink-absorbing coating to the side of the aluminum-plated layer that is away from the laser-molded layer, heat to unseal and cure, and form an ink-absorbing coating.

[0033] In summary, this application includes at least the following beneficial technical effects:

[0034] In this application, the ink-absorbing coating of the vacuum electroplated laser DTF white ink heat transfer film is made of a specific ratio of hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane, aminosilane coupling agent-modified nano-silica, blocked isocyanate curing agent, polyether graft-modified PVA, and other basic additives. Through the synergistic effect of each component, a vacuum electroplated laser DTF white ink heat transfer film with clear and complete patterns, distinct boundaries, heat resistance, and excellent resistance to low-temperature cracking can be obtained. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of a vacuum electroplated laser DTF white ink hot stamping film according to an embodiment of this application.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1. Base film layer; 2. Centrifugal layer; 3. Laser lithography layer; 4. Aluminum plating layer; 5. Ink-absorbing coating. Detailed Implementation

[0038] The following section provides further explanation of this application in conjunction with specific experiments.

[0039] Preparation Example

[0040]

Preparation Example 1-1

[0041] A hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is prepared from 33 kg of polytetrahydrofuran ether glycol 2000, 12 kg of polyethylene glycol 1500, 8.5 kg of polypropylene glycol 1500, 5.8 kg of hydroxyethyl-terminated polydimethylsiloxane with a viscosity of 350 mPa·s, 12.8 kg of isophorone diisocyanate, 1 kg of 2,2-dimethylolpropionic acid, 0.8 kg of ethylenediamine, 0.05 kg of dibutyltin dilaurate, 10 kg of acetone, and 25 kg of water.

[0042] In this preparation example, the preparation method of hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is as follows:

[0043] Polytetrahydrofuran ether glycol, polyethylene glycol, polypropylene glycol, hydroxyethyl-terminated polydimethylsiloxane, and 2,2-dimethylolpropionic acid were dissolved at 50°C, dehydrated under vacuum, and then cooled to 75°C. Isophorone diisocyanate and dibutyltin dilaurate were added and reacted for 3 hours. Then, the temperature was lowered to 45°C, acetone and ethylenediamine were added, the mixture was stirred and water was added, and finally, acetone was recovered by distillation to obtain hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane.

[0044]

Preparation Examples 1-2

[0045] A hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is prepared from 38 kg of polytetrahydrofuran ether glycol 2000, 16 kg of polyethylene glycol 1500, 9.8 kg of polypropylene glycol 1500, 6.5 kg of hydroxyethyl-terminated polydimethylsiloxane with a viscosity of 350 mPa·s, 14.2 kg of isophorone diisocyanate, 2 kg of 2,2-dimethylolpropionic acid, 1.2 kg of ethylenediamine, 0.08 kg of dibutyltin dilaurate, 15 kg of acetone, and 30 kg of water.

[0046] In this preparation example, the preparation method of hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is as follows:

[0047] Polytetrahydrofuran ether glycol, polyethylene glycol, polypropylene glycol, hydroxyethyl-terminated polydimethylsiloxane, and 2,2-dimethylolpropionic acid were dissolved at 55°C, dehydrated under vacuum, and then cooled to 80°C. Isophorone diisocyanate and dibutyltin dilaurate were added and reacted for 2.5 h. Then the temperature was lowered to 45°C, acetone and ethylenediamine were added, the mixture was stirred and water was added, and finally the acetone was recovered by distillation to obtain hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane.

[0048]

Preparation Examples 1-3

[0049] A hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane differs from [Preparation Example 1-1] in that the amount of hydroxyethyl-terminated polydimethylsiloxane used is 10 kg.

[0050]

Preparation Examples 1-4

[0051] A hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane differs from [Preparation Example 1-1] in that hydroxyethyl-terminated polydimethylsiloxane is not added.

[0052]

Preparation Example 2-1

[0053] A polyether-grafted modified PVA is obtained by alcoholysis of a modified polyvinyl acetate prepared by the following weight ratios: 65 kg vinyl acetate, 35 kg allyl epoxy-terminated polyoxyethylene polyoxypropylene ether (the degree of polymerization of the polyoxyethylene segment is 25 and that of the polyoxypropylene segment is 15), 3 kg emulsifier, 4 kg initiator (i.e., a 30% ammonium persulfate aqueous solution), 0.1 kg dodecyl mercaptan, 0.2 kg sodium bicarbonate, and 100 kg water; wherein the emulsifier includes sodium dodecyl sulfate and OP-10, and the weight ratio of sodium dodecyl sulfate to OP-10 is 1:1.

[0054] In this preparation example, the preparation method of polyether grafted modified PVA includes the following steps:

[0055] The emulsifier is dissolved in water accounting for 70% of the total weight of water, and then vinyl acetate and allyl epoxy-terminated polyoxyethylene polyoxypropylene ether are added to form a pre-emulsion at a shear rate of 1000 r / min.

[0056] Dissolve sodium bicarbonate in the remaining water until homogeneous, then add 10% of the total weight of the pre-emulsion and 30% of the total weight of the initiator to obtain the seed emulsion.

[0057] The remaining pre-emulsion and the remaining initiator were added dropwise to the seed emulsion simultaneously, and the reaction temperature was controlled at 75℃. The addition time was controlled at 2-2.5h. After the addition was completed, the temperature was raised to 85℃ and kept at that temperature for 1.5h. Then, the mixture was cooled, filtered to remove impurities, and the modified polyvinyl acetate emulsion was obtained.

[0058] Modified polyvinyl acetate emulsion was broken down and then centrifuged to obtain modified polyvinyl acetate.

[0059] Modified polyvinyl acetate was added to a solution containing 15% methanol and 0.2% sodium hydroxide, and the solution was heated to 60°C for 30 minutes to undergo alcoholysis, thereby obtaining polyether-grafted modified PVA.

[0060]

Preparation Example 2-2

[0061] A polyether-grafted modified PVA is obtained by alcoholysis of a modified polyvinyl acetate prepared by the following weight ratios: 75 kg vinyl acetate, 25 kg allyl epoxy-terminated polyoxyethylene polyoxypropylene ether (the degree of polymerization of the polyoxyethylene segment is 20 and the degree of polymerization of the polyoxypropylene segment is 10), 4 kg emulsifier, 5 kg initiator (i.e., a 30% ammonium persulfate aqueous solution), 0.3 kg dodecyl mercaptan, 0.3 kg sodium bicarbonate, and 100 kg water; wherein the emulsifier includes sodium dodecyl sulfate and OP-10, and the weight ratio of sodium dodecyl sulfate to OP-10 is 1:1.

[0062] In this preparation example, the preparation method of polyether grafted modified PVA includes the following steps:

[0063] The emulsifier is dissolved in water accounting for 80% of the total weight of water, and then vinyl acetate and allyl epoxy-terminated polyoxyethylene polyoxypropylene ether are added to form a pre-emulsion at a shear rate of 1000 r / min.

[0064] Sodium bicarbonate was dissolved evenly in the remaining water, and then 15% of the pre-emulsion and 35% of the initiator were added to obtain the seed emulsion.

[0065] The remaining pre-emulsion and the remaining initiator were added dropwise to the seed emulsion simultaneously, and the reaction temperature was controlled at 80℃. The addition time was controlled at 2-2.5h. After the addition was completed, the temperature was raised to 90℃ and kept at that temperature for 1h. Then the mixture was cooled, filtered and impurities were removed to obtain the modified polyvinyl acetate emulsion.

[0066] Modified polyvinyl acetate emulsion was broken down and then centrifuged to obtain modified polyvinyl acetate.

[0067] Modified polyvinyl acetate was added to a solution of 20% methanol and 0.5% sodium hydroxide, and the solution was heated to 60°C for 30 minutes to undergo alcoholysis, thereby obtaining polyether-grafted modified PVA.

[0068]

Preparation Examples 2-3

[0069] A polyether-grafted modified PVA differs from [Preparation Example 2-1] in that the amount of vinyl acetate and allyl epoxy-terminated polyoxyethylene polyoxypropylene ether is both 50 kg.

[0070]

Preparation Examples 2-4

[0071] A polyether-grafted modified PVA differs from that in [Preparation Example 2-1] in that allyl epoxy-terminated polyoxyethylene polyoxypropylene ether is replaced with an equal mass of vinyl acetate.

[0072]

Preparation Example 3-1

[0073] An ink-absorbing coating is prepared by uniformly mixing 40 wt% of hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane obtained in Preparation Example 1-1, 10 wt% of aminosilane coupling agent-modified nano-silica, 6.8 wt% of blocked isocyanate curing agent (80℃ low-temperature unblocking blocked isocyanate PT-1080Y), 0.1 wt% wetting agent (wetting agent X-405), 0.1 wt% defoamer (polyether defoamer), 0.5 wt% leveling agent (ZY-1603 silicone leveling agent), 0.5 wt% sodium polyacrylate dispersant (Guangdong Fengte New Materials Co., Ltd. waterborne sodium polyacrylate dispersant 8491), and the balance being a 15% polyether-grafted modified PVA aqueous solution. The 15% polyether-grafted modified PVA aqueous solution is prepared by mixing polyether-grafted modified PVA obtained in Preparation Example 2-1 with water.

[0074] The aminosilane coupling agent modified nano-silica was obtained by dissolving 0.02 kg of silane coupling agent KH550 in an ethanol solution, reacting it with 10 kg of nano-silica at 50°C for 2 h, and then filtering, washing, and drying.

[0075]

Preparation Example 3-2

[0076] An ink-absorbing coating is prepared by uniformly mixing 50 wt% of hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane prepared in [Preparation Examples 1-2], 15 wt% of aminosilane coupling agent-modified nano-silica, 8.2 wt% of blocked isocyanate curing agent (80℃ low-temperature unblocking blocked isocyanate PT-1080Y), 1 wt% wetting agent (wetting agent X-405), 0.8 wt% defoamer (polyether defoamer), 0.1 wt% leveling agent (ZY-1603 silicone leveling agent), 2 wt% sodium polyacrylate dispersant (Guangdong Fengte New Materials Co., Ltd. waterborne sodium polyacrylate dispersant 8491), and the balance being a 15% polyether-grafted modified PVA aqueous solution. The 15% polyether-grafted modified PVA aqueous solution is prepared by mixing the polyether-grafted modified PVA prepared in [Preparation Examples 2-2] with water.

[0077] The aminosilane coupling agent modified nano-silica was obtained by dissolving 0.02 kg of silane coupling agent KH550 in an ethanol solution, reacting it with 10 kg of nano-silica at 50°C for 2 h, and then filtering, washing, and drying.

[0078]

Preparation Example 3-3

[0079] An ink-absorbing coating differs from [Preparation Example 3-1] in that the hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is prepared using the hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane obtained in [Preparation Example 1-3].

[0080]

Preparation Examples 3-4

[0081] An ink-absorbing coating differs from [Preparation Example 3-1] in that the hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is prepared using the hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane obtained in [Preparation Example 1-4].

[0082]

Preparation Examples 3-5

[0083] An ink-absorbing coating differs from [Preparation Example 3-1] in that: a 15% (w / w) aqueous solution of polyether-grafted modified PVA is prepared by mixing the polyether-grafted modified PVA obtained in [Preparation Example 2-3] with water.

[0084]

Preparation Examples 3-6

[0085] An ink-absorbing coating differs from [Preparation Example 3-1] in that: a 15% (w / w) aqueous solution of polyether-grafted modified PVA is prepared by mixing polyether-grafted modified PVA obtained in [Preparation Example 2-4] with water.

[0086]

Preparation Examples 3-7

[0087] An ink-absorbing coating differs from [Preparation Example 3-1] in that the hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is replaced by an equal mass of 15% polyether-grafted modified PVA aqueous solution.

[0088]

Preparation Examples 3-8

[0089] An ink-absorbing coating differs from [Preparation Example 3-1] in that: an equal mass of hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is used instead of a 15% (w / w) polyether-grafted modified PVA aqueous solution.

[0090] Example

[0091]

Example 1

[0092] A vacuum electroplated laser DTF white ink heat transfer film, as referenced Figure 1 It includes a PET base film layer, a release layer, a laser molding layer, an aluminum plating layer, and an ink-absorbing coating layer arranged sequentially.

[0093] A UV release agent (US-400) is coated on the surface of the PET base film to form a release layer;

[0094] A laser molding material is coated on the side of the release layer opposite to the base film layer and cured (curing energy is 800 mJ / cm). 2 After that, a laser-molded layer with a thickness of 1μm is formed; wherein, the laser-molded coating includes 45kg of difunctional polyurethane acrylic resin (Lankeluo L-6206), 5.6kg of hexafunctional polyurethane acrylic resin (Lankeluo L-6605), 3.8kg of vinylmethyldimethoxysilane grafted modified nano-silica, 15kg of active monomers and 0.1kg of photoinitiator TPO, the active monomers specifically include isobornyl acrylate, ethoxyethoxyethyl acrylate, tetrahydrofuran acrylate and hydroxyethyl acrylate, the weight ratio of isobornyl acrylate, ethoxyethoxyethyl acrylate, tetrahydrofuran acrylate and hydroxyethyl acrylate is 1:3:3:3;

[0095] Aluminum is vapor-deposited on the side of the laser-molded layer away from the release layer to form an aluminum-plated layer; during aluminum vapor deposition, the evaporation rate of aluminum is controlled at 1 nm / s, and the thickness of the aluminum-plated layer is controlled at 50 nm.

[0096] The ink-absorbing coating prepared in [Preparation Example 3-1] is applied to the side of the aluminum-plated layer away from the laser-molded layer, and then heated to 85°C to unseal and cure, forming an ink-absorbing coating.

[0097]

Example 2

[0098] A vacuum electroplated laser DTF white ink heat transfer film differs from [Example 1] in that the ink-absorbing coating is the ink-absorbing coating prepared in [Preparation Example 3-2].

[0099] Comparative Example

[0100] Comparative Example 1

[0101] A vacuum electroplated laser DTF white ink heat transfer film differs from [Example 1] in that the ink-absorbing coating is the ink-absorbing coating prepared in [Preparation Example 3-3].

[0102] Comparative Example 2

[0103] A vacuum electroplated laser DTF white ink heat transfer film differs from [Example 1] in that the ink-absorbing coating is the ink-absorbing coating prepared in [Preparation Examples 3-4].

[0104] Comparative Example 3

[0105] A vacuum electroplated laser DTF white ink heat transfer film differs from [Example 1] in that the ink-absorbing coating is the ink-absorbing coating prepared in [Preparation Examples 3-5].

[0106] Comparative Example 4

[0107] A vacuum electroplated laser DTF white ink heat transfer film differs from [Example 1] in that the ink-absorbing coating is the ink-absorbing coating prepared in [Preparation Examples 3-6].

[0108] Comparative Example 5

[0109] A vacuum electroplated laser DTF white ink heat transfer film differs from [Example 1] in that the ink-absorbing coating is the ink-absorbing coating prepared in [Preparation Examples 3-7].

[0110] Comparative Example 6

[0111] A vacuum electroplated laser DTF white ink heat transfer film differs from [Example 1] in that the ink-absorbing coating is the ink-absorbing coating prepared in [Preparation Examples 3-8].

[0112] Performance testing

[0113] Preparation of hot stamping samples: The white ink hot stamping films prepared in each embodiment and comparative example were printed with test patterns using conventional printing methods. The samples were left to air dry naturally. Then, 400-mesh hot melt powder was evenly sprinkled on the surface of the pattern. Excess powder was shaken off, and the sample was heated to 105°C for 30 seconds to melt the hot melt adhesive powder into a film. The pattern was cut out, leaving a 5mm white edge. The hot stamping machine was preheated to the set temperature. A cotton cloth was laid flat to make it smooth and wrinkle-free. The pattern side was placed face down on the cotton cloth, and a heat-resistant silicone pad was covered and hot-pressed evenly at 150°C for 10 seconds. After hot pressing, the PET base film layer was peeled off while it was still hot. The samples were left to stand for 24 hours to obtain hot stamping samples (10cm*20cm) after the white ink hot stamping film transfer of each embodiment and comparative example.

[0114] 1. Evaluation of hot stamping effect: Randomly select 10 hot stamping samples corresponding to each embodiment and comparative example, observe whether the hot stamping pattern is clear and complete, and whether the boundary is distinct, and record the number of hot stamping patterns that are clear and complete and have distinct boundaries (qualified).

[0115] 2. Resistance to low temperature cracking: Ten hot stamping samples corresponding to each example and comparative example were randomly selected and placed in an environment of -30℃ for 72 hours. After returning to room temperature, the hot stamping samples were stretched to 30cm along the length direction and placed for 1 hour. The hot stamping pattern was observed to see if cracks appeared and the number of cracks in the hot stamping pattern was recorded.

[0116] 3. Heat resistance: Ten hot stamping samples corresponding to each embodiment and comparative example were randomly selected and placed in an environment of 60°C for 168 hours. After being taken out and cooled to room temperature, the hot stamping samples were stretched to 30 cm along the length direction and placed for 1 hour. The hot stamping pattern was observed to see if cracks appeared and the number of cracks in the hot stamping pattern was recorded.

[0117] Table 1

[0118]

[0119] Based on Examples 1-2 and the test data in Table 1, it can be seen that in this application, the ink-absorbing coating uses hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane and polyether-grafted modified PVA as the main film-forming materials and binders. Combined with aminosilane coupling agent-modified nano-silica and basic additives, it is possible to obtain a vacuum electroplating laser DTF white ink heat transfer film with clear and complete patterns, distinct boundaries, heat resistance, and excellent resistance to low-temperature cracking.

[0120] Based on the test data in Example 1, Comparative Examples 1-2, and Table 1, it can be seen that excessive use of hydroxyethyl-terminated polydimethylsiloxane in waterborne polyurethane modified with hydroxyethyl-terminated polydimethylsiloxane will affect the clarity and integrity of the printed pattern. In addition, without the addition of hydroxyethyl-terminated polydimethylsiloxane, the heat resistance of the pattern decreases. That is, only when the amount of hydroxyethyl-terminated polydimethylsiloxane modified with hydroxyethyl-terminated polyurethane is within the range of this application can a vacuum electroplating laser DTF white ink hot stamping film with clear and complete patterns, distinct boundaries, heat resistance, and excellent resistance to low-temperature cracking be obtained.

[0121] Based on the test data in Example 1, Comparative Examples 3-4, and Table 1, it can be seen that excessive allyl epoxy polyoxyethylene polyoxypropylene ether in polyether-grafted modified PVA will affect the clarity and integrity of the printed pattern. In addition, without the addition of allyl epoxy polyoxyethylene polyoxypropylene ether, the compatibility between polyether-grafted modified PVA and hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane will also lead to unclear and incomplete printed patterns. At the same time, it will also affect the low-temperature crack resistance of the pattern, which is not conducive to obtaining a vacuum electroplated laser DTF white ink hot stamping film with clear and complete patterns, distinct boundaries, heat resistance and excellent low-temperature crack resistance.

[0122] Based on the test data in Example 1, Comparative Examples 5-6, and Table 1, it can be seen that using hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane or polyether-grafted modified PVA as the main film-forming material and adhesive for ink-absorbing coatings alone is not conducive to obtaining vacuum electroplating laser DTF white ink heat transfer film with clear and complete patterns, distinct boundaries, heat resistance, and excellent resistance to low-temperature cracking.

[0123] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this specific embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A vacuum electroplated laser DTF white ink heat transfer film, characterized in that: It includes a base film layer, a release layer, a laser molding layer, an aluminum plating layer, and an ink-absorbing coating layer arranged sequentially. The ink-absorbing coating is an ink-absorbing coating, which is prepared by using 40-50wt% hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane, 10-15wt% aminosilane coupling agent-modified nano-silica, 6.8-8.2wt% blocked isocyanate curing agent, 0.1-1.0wt% wetting agent, 0.1-0.8wt% defoamer, 0.1-0.5wt% leveling agent, 0.5-2.0wt% dispersant, and the balance being 10-15% polyether-grafted modified PVA aqueous solution. The hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is prepared from polytetrahydrofuran ether glycol, polyethylene glycol, polypropylene glycol, hydroxyethyl-terminated polydimethylsiloxane, diisocyanate, 2,2-dimethylolpropionic acid, neutralizing agent, catalyst, acetone and water in a weight ratio of (33-38), (12-16): (8.5-9.8): (5.8-6.5): (12.8-14.2): (1-2): (0.8-1.2): (0.05-0.08): (10-15): (25-30). The polyether-grafted modified PVA is obtained by alcoholysis of modified polyvinyl acetate, alkenyl polyether, emulsifier, initiator, chain transfer agent, pH adjuster and water in a weight ratio of (65-75):(25-35):(3-4):(4-5):(0.1-0.3):(0.2-0.3):

100. The alkenyl polyether is an allyl epoxy-terminated polyoxyethylene polyoxypropylene ether, wherein the degree of polymerization of the polyoxyethylene segment is 20-25 and the degree of polymerization of the polyoxypropylene segment is 10-15.

2. The vacuum electroplating laser DTF white ink heat transfer film according to claim 1, characterized in that: The number average molecular weights of the polytetrahydrofuran ether diol, polyethylene glycol, and polypropylene glycol are all in the range of 1500-2500.

3. The vacuum electroplating laser DTF white ink heat transfer film according to claim 1, characterized in that: The viscosity of the hydroxyethyl-terminated polydimethylsiloxane is 340-380 mPa·s.

4. A vacuum electroplated laser DTF white ink heat transfer film according to any one of claims 1-3, characterized in that: The preparation method of the hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane is as follows: Polytetrahydrofuran ether glycol, polyethylene glycol, polypropylene glycol, hydroxyethyl-terminated polydimethylsiloxane, and 2,2-dimethylolpropionic acid were dissolved at 50-55℃, dehydrated under vacuum, and then cooled to 75-80℃. Diisocyanate and catalyst were added and reacted for 2.5-3 hours. The mixture was then cooled to 45℃, acetone and a neutralizing agent were added, and water was added while stirring. Finally, acetone was recovered by distillation to obtain hydroxyethyl-terminated polydimethylsiloxane-modified waterborne polyurethane.

5. The vacuum electroplating laser DTF white ink heat transfer film according to claim 1, characterized in that: The emulsifier comprises sodium dodecyl sulfate and OP-10, wherein the weight ratio of sodium dodecyl sulfate to OP-10 is 1:(1-1.5).

6. The vacuum electroplating laser DTF white ink heat transfer film according to claim 1, characterized in that: The initiator is a 25-35% persulfate aqueous solution.

7. A vacuum electroplated laser DTF white ink heat transfer film according to any one of claims 1-3 and 5-6, characterized in that: The preparation method of the polyether grafted modified PVA includes the following steps: Dissolve the emulsifier in water that accounts for 70-80% of the total weight of water, then add vinyl acetate and alkenyl polyether, and form a pre-emulsion at a shear rate of 1000-2000 r / min. Dissolve the pH adjuster in the remaining water until homogeneous, then add 10-15% of the pre-emulsion by weight and 30-35% of the initiator by weight to obtain the seed emulsion. The remaining pre-emulsion and the remaining initiator were added dropwise to the seed emulsion simultaneously, and the reaction temperature was controlled at 75-80℃. After the addition was completed, the temperature was raised to 85-90℃ and kept for 1-1.5 hours. Then the mixture was cooled, filtered to remove impurities, and the modified polyvinyl acetate emulsion was obtained. Modified polyvinyl acetate emulsion was broken down and then centrifuged to obtain modified polyvinyl acetate. Modified polyvinyl acetate was subjected to alcoholysis to obtain modified polyvinyl alcohol.

8. A method for preparing a vacuum electroplated laser DTF white ink hot stamping film as described in any one of claims 1-7, characterized in that, Includes the following steps: A release agent is applied to the surface of the base film layer to form a release layer; Laser molding material is coated on the side of the release layer away from the base film layer, and after curing, a laser molding layer is formed. Aluminum is vapor-deposited on the side of the laser-molded layer that is away from the release layer to form an aluminum-plated layer; Apply ink-absorbing coating to the side of the aluminum-plated layer that is away from the laser-molded layer, heat to unseal and cure, and form an ink-absorbing coating.

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