Dtf white ink transfer film with surface texture

Abstract

The application discloses a DTF white ink pyrography film with surface lines and relates to the technical field of printing and printing materials. The DTF white ink pyrography film with surface lines comprises a PET base film layer, a release layer and an ink absorption coating layer which are sequentially arranged in layers, the PET base film layer is provided with a UV-cured surface line, the release layer is coated by a release agent, and the ink absorption coating layer is coated by an ink absorption coating material, the release agent comprises the following raw materials in parts by weight: 50-80 parts of a hydroxyl-containing acrylic resin, 9-17 parts of a curing agent, 10-18 parts of a fluorocarbon resin, 4-7 parts of modified nano silicon dioxide, 1-3 parts of a surfactant, 8-13 parts of toluene and 9-16 parts of ethyl acetate. The DTF white ink pyrography film prepared by the application can realize peeling at normal temperature (about 20 DEG C) and high temperature (about 150 DEG C).

Description

Technical Field

[0001] This invention relates to the technical field of printing materials, and in particular to a DTF white ink heat transfer film with surface texture. Background Technology

[0002] Heat transfer film is a material used to transfer text or patterns onto the surface of other objects using high temperatures. White ink heat transfer is a highly efficient and vibrant heat transfer technology that uses high temperature and pressure to transfer white ink material onto the surface of fabric, forming a stable layer. It is suitable for various materials such as shoes, hats, canvas bags, and clothing. DTF white ink heat transfer film is a substrate specifically designed for white ink heat transfer printing, directly determining the transfer quality of the white ink heat transfer. It is mainly used in the apparel industry.

[0003] In white ink heat transfer printing, the desired pattern is typically designed beforehand on a computer, transferred to a DTF printer, and printed onto a DTF heat transfer film. Then, hot melt adhesive powder is applied using a powder shaker, followed by high-temperature baking to fix the color. Finally, the hot melt adhesive powder is melted at high temperature, and the pattern is transferred onto the fabric using heat transfer printing. In this process, the DTF heat transfer film acts as an intermediary carrier. To obtain clear, stable, and flawless transferred images, certain requirements are placed on the heat transfer film's ink absorption, adhesion, and anti-blocking properties.

[0004] Common heat transfer films mainly consist of a PET base layer, a release layer, and an ink-absorbing layer. The release layer ensures that the pattern or text can be smoothly transferred to the substrate during the heat transfer process and protects the ink, enhancing its durability. Existing release layers generally require cooling after transfer before the heat transfer film can be peeled off, leading to reduced transfer efficiency. Therefore, a DTF heat transfer film that can be peeled off at both room temperature (around 20℃) and high temperature (around 150℃) is needed to improve transfer efficiency. Summary of the Invention

[0005] In order to obtain a DTF white ink heat transfer film that can be peeled off at both room temperature (around 20°C) and high temperature (around 150°C), this application provides a DTF white ink heat transfer film with surface texture.

[0006] The technical solution for a textured DTF white ink heat transfer film provided in this application is as follows:

[0007] A DTF white ink heat transfer film with surface texture includes a PET base film layer, a release layer, and an ink-absorbing coating layer stacked sequentially. The PET base film layer has a UV-curable surface texture. The release layer is coated with a release agent, and the ink-absorbing coating layer is coated with an ink-absorbing paint. The release agent comprises the following raw materials in parts by weight:

[0008] 50-80 parts of hydroxyl-containing acrylic resin;

[0009] 9-17 parts of curing agent;

[0010] 10-18 parts of fluorocarbon resin;

[0011] 4-7 parts of modified nano-silica;

[0012] 1-3 parts surfactant;

[0013] 8-13 parts of toluene;

[0014] 9-16 parts of ethyl acetate;

[0015] The modified nano-silica is prepared by the following steps: pouring nano-silica into a flask, adding concentrated nitric acid and letting it stand at room temperature for 10-20 minutes, pouring out the nitric acid and leaving acidified nano-silica in the flask, heating for 1-2 minutes to evaporate the nitric acid; then adding anhydrous ethanol to the flask, heating under reflux at 95-100℃ for 20-30 minutes with an electronic heating mantle, evaporating the ethanol to obtain modified nano-silica, wherein the volume of concentrated nitric acid (ml): the volume of anhydrous ethanol (ml): the mass of nano-silica (g) = 10-15: 20-30: 1.

[0016] By adopting the above technical solution, the release layer is composed of a film-forming substance and a release agent. The film-forming substance is composed of a compound of hydroxyl-containing acrylic resin and fluorocarbon resin. Acrylic resin has good film-forming properties and flowability, while fluorocarbon resin, with a strong CF bond backbone, has good high-temperature resistance and weather resistance. After compounding, the film-forming performance is good, and it is easy to adjust the uniformity and adhesion. The release agent is modified nano-silica, which has low surface tension, good peeling performance, and good adhesion to the film-forming substance. The addition of surfactants can be adsorbed on the surface of modified nano-silica, thereby promoting the dispersion of modified nano-silica and improving the dispersion uniformity of the release layer. The addition of solvents can reduce viscosity and facilitate the curing and film formation of the release layer. Through the combination of raw materials, the surface tension of the release layer is low, and it can spread and adhere well on the PET base film. At the same time, the adhesion between the release layer and the PET base film is small, and peeling can be achieved at both room temperature (around 20℃) and high temperature (around 150℃).

[0017] Modified nano-silica was selected, and acidification with nitric acid exposed more silanol groups, enhancing the interfacial bonding with the film-forming resin. Esterification with ethanol reduced the number of hydroxyl groups, improving the dispersibility of the modified nano-silica in the film-forming resin and enhancing the uniformity and integrity of the release layer. Modification also lowered the surface energy of the nano-silica, optimizing peel performance, improving transfer results, and producing clear and complete transfer patterns.

[0018] Furthermore, the hydroxyl-containing acrylic resin comprises the following raw materials in parts by weight:

[0019] 10-15 parts of methyl methacrylate;

[0020] 8-12 parts of isobornyl methacrylate;

[0021] 25-40 parts of isooctyl acrylate;

[0022] 1-2 parts of 2-mercaptopropionic acid;

[0023] 13-27 parts of modified prepolymer;

[0024] 2-5 parts of initiator;

[0025] Solvent 25-35 parts;

[0026] The modified prepolymer is a modified prepolymer synthesized from acrylic acid and glycidyl tert-carbonate.

[0027] By adopting the above technical solution, glycidyl tert-carbonate is added to the raw material of acrylic resin for modification, which reduces the viscosity of the hydroxyl-containing acrylic resin, thereby reducing the bonding force between the acrylic resin and the PET base film layer, making it easier to peel off. The introduction of hydroxyl groups increases the crosslinking density, resulting in a denser and fuller coating.

[0028] Furthermore, the modified prepolymer is prepared through the following steps:

[0029] Add 60-70 parts by weight of glycidyl tert-carbonate, 0.05-0.2 parts by weight of stannous octoate, and 0.4-0.8 parts by weight of antioxidant to a three-necked flask, purge with nitrogen and heat to 80-85°C, then add dropwise a mixture of 20-30 parts by weight of acrylic acid and 0.01-0.05 parts by weight of polymerization inhibitor over 15-20 minutes. Maintain the reaction at 90-95°C for 2 hours, and when the acid value is ≤12 mg KOH / g, cool down and discharge to obtain the modified prepolymer.

[0030] By adopting the above technical solution, hydroxyl groups are generated by the ring-opening reaction of the carboxyl group of acrylic acid and the epoxy group of glycidyl tert-carbonate under a catalyst, thereby introducing hydroxyl groups into acrylic resin. Furthermore, a modified prepolymer is first generated and then undergoes free radical polymerization with other acrylate monomers, successfully grafting glycidyl tert-carbonate into the acrylic polymer chain segment, thus improving the grafting modification rate.

[0031] Furthermore, the fluorocarbon resin is one or more of polytetrafluoroethylene, polyvinylidene fluoride, and fluoroolefin-vinyl ether copolymer.

[0032] Furthermore, the curing agent is selected from one or both of melamine-based curing agents and isocyanate-based curing agents.

[0033] Furthermore, the surfactant is a mixture of stearic acid and Span 60 in a weight ratio of (60-70):(40-30).

[0034] By adopting the above technical solution, the compounded surfactant has good dispersibility for modified nano-silica, and is beneficial to reducing the hydrophilicity of modified nano-silica, and has good compatibility with the film-forming resin system.

[0035] Furthermore, the ink-absorbing coating comprises the following raw materials in parts by weight: 50-65 parts of polyvinyl alcohol; 18-27 parts of waterborne polyurethane resin; 20-38 parts of fumed silica; 3-5 parts of boric acid; and 0.3-0.8 parts of wetting and leveling agent.

[0036] By adopting the above technical solution, polyvinyl alcohol (PVA) provides excellent film-forming properties, strength, and ink affinity. Furthermore, the cross-linking effect promoted by boric acid enhances its water resistance and strength. Fumed silica, as the primary ink absorber, enables rapid ink absorption and ensures image clarity. The wetting and leveling agent ensures uniform spreading of the coating on the release layer. The ink-absorbing layer prepared from these raw materials has a smooth and flat surface, exhibiting excellent adhesion to the release layer.

[0037] Furthermore, the initiator is selected from one or both of tert-butyl peroxide benzoate and tert-butyl peroxide acetate.

[0038] Furthermore, the hydroxyl-containing acrylic resin is prepared by the following steps:

[0039] In a four-necked flask, add solvent, modified prepolymer, and 1 / 3 of the initiator. Purge with nitrogen and heat to a uniform temperature. Mix methyl methacrylate, isobornyl methacrylate, isooctyl acrylate, and the remaining initiator to form a homogeneous mixture and place it in a feeding funnel. When the solvent refluxes, add 10% of the mixture dropwise to the four-necked flask over 10-15 minutes. Continue heating to 137-142°C and, while maintaining the temperature, add the remaining mixture dropwise at a uniform rate over 3.5-4 hours. Stir and maintain the temperature for 3-4 hours. Cool and filter to obtain hydroxyl-containing acrylic resin.

[0040] Furthermore, the DTF white ink heat transfer film is prepared through the following steps:

[0041] Surface textures are created on PET film using UV curing texturing technology to obtain a PET base film layer;

[0042] A release layer is obtained by applying a release agent onto a PET base film using an anilox roller coating method.

[0043] An ink-absorbing coating is obtained by applying an ink-absorbing coating material onto the release layer using a micro-concave roller coating method, forming a DTF white ink heat transfer film.

[0044] By adopting the above technical solution, surface textures are prepared onto PET film using UV texturing technology. As the release layer and PET film adhere, the textures are printed onto the release layer. Thus, after transfer and peeling, the graphic surface on the fabric has its own decorative textures such as grating and cat's eye patterns.

[0045] In summary, this application has the following beneficial effects:

[0046] 1. The release layer consists of a film-forming substance and a release agent. The film-forming substance is a blend of hydroxyl-containing acrylic resin and fluorocarbon resin. Acrylic resin has good film-forming properties and flowability, while fluorocarbon resin, with a strong CF bond backbone, has good high-temperature resistance and weather resistance. The blended product exhibits good film-forming properties and is easy to adjust for uniformity and adhesion. The release agent is modified nano-silica, which has low surface tension, good peeling properties, and good adhesion to the film-forming substance. The addition of surfactants allows them to be adsorbed onto the surface of modified nano-silica, promoting its dispersion and improving the uniformity of the release layer. The addition of solvents reduces viscosity, facilitating the curing and film formation of the release layer. Through the combination of raw materials, the release layer has low surface tension and can spread and adhere well to the PET base film. Simultaneously, the adhesion between the release layer and the PET base film is low, enabling peeling at both room temperature (around 20℃) and high temperature (around 150℃).

[0047] 2. Modified nano-silica is selected. Acidification of the nano-silica with nitric acid exposes more silanol groups, enhancing the interfacial bonding with the film-forming resin. Esterification with ethanol reduces the number of hydroxyl groups, improving the dispersibility of the modified nano-silica in the film-forming resin and enhancing the uniformity and integrity of the release layer. Modification lowers the surface energy of the nano-silica, thereby optimizing peel performance, improving the transfer effect, and resulting in a clear and complete transfer pattern.

[0048] 3. Adding glycidyl tert-carbonate to the raw material of acrylic resin for modification reduces the viscosity of the hydroxyl-containing acrylic resin, thereby reducing the bonding force between the acrylic resin and the PET base film layer, making it easier to peel off. The introduction of hydroxyl groups increases the crosslinking density, resulting in a denser and fuller coating. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the structure of the DTF white ink heat transfer film of this application.

[0050] Explanation of reference numerals in the attached figures:

[0051] 1. PET base film layer; 2. Release layer; 3. Ink-absorbing coating. Detailed Implementation

[0052] The present application will be further described in detail below with reference to Examples 1-5 and Comparative Examples 1-2.

[0053] Preparation Example

[0054] Preparation Example 1

[0055] A hydroxyl-containing acrylic resin comprises the following raw materials in parts by weight:

[0056] 10 parts of methyl methacrylate;

[0057] 8 parts of isobornyl methacrylate;

[0058] 25 parts of isooctyl acrylate;

[0059] 1 part of 2-mercaptopropionic acid;

[0060] Thirteen parts of modified prepolymer were selected, which were modified prepolymers synthesized from acrylic acid and glycidyl tert-carbonate.

[0061] Two parts of initiator, specifically tert-butyl peroxide benzoate;

[0062] 25 parts solvent, specifically xylene.

[0063] Hydroxyl-containing acrylic resins are prepared by the following steps:

[0064] 60 parts by weight of glycidyl tert-carbonate, 0.05 parts by weight of stannous octoate, and 0.4 parts by weight of antioxidant were added to a three-necked flask. Nitrogen gas was introduced and the temperature was raised to 80°C. A mixture of 20 parts by weight of acrylic acid and 0.01 parts by weight of polymerization inhibitor was added dropwise over a period of 15 minutes. The mixture was kept at 90°C for 2 hours. When the acid value was measured to be ≤12 mg KOH / g, the temperature was lowered and the modified prepolymer was discharged.

[0065] Solvent, modified prepolymer, and 1 / 3 of the initiator were added to a four-necked flask. Nitrogen gas was introduced and the flask was heated. Methyl methacrylate, isobornyl methacrylate, isooctyl acrylate, and the remaining initiator were mixed evenly to form a mixture, which was then placed in a feeding funnel. When the solvent refluxed, 10% of the mixture was added dropwise to the four-necked flask over 10 minutes. The temperature was then raised to 137°C, and the remaining mixture was added dropwise at a uniform rate over 3.5 hours while maintaining the temperature. The mixture was stirred and kept at the temperature for 3 hours. After cooling and filtration, the hydroxyl-containing acrylic resin was obtained.

[0066] Preparation Example 2

[0067] 15 parts of methyl methacrylate;

[0068] 12 parts of isobornyl methacrylate;

[0069] 40 parts of isooctyl acrylate;

[0070] 2 parts of 2-mercaptopropionic acid;

[0071] 27 parts of modified prepolymer were selected, which were modified prepolymers synthesized from acrylic acid and glycidyl tert-carbonate;

[0072] Five parts of initiator, specifically tert-butyl peroxide acetate;

[0073] The solvent is 35 parts, specifically 25 parts xylene and 10 parts acetone.

[0074] Hydroxyl-containing acrylic resins are prepared by the following steps:

[0075] 70 parts by weight of glycidyl tert-carbonate, 0.2 parts by weight of stannous octoate, and 0.8 parts by weight of antioxidant were added to a three-necked flask. Nitrogen gas was introduced and the temperature was raised to 85°C. A mixture of 30 parts by weight of acrylic acid and 0.05 parts by weight of polymerization inhibitor was added dropwise over a period of 20 min. The mixture was kept at 95°C for 2 h. When the acid value was measured to be ≤12 mg KOH / g, the temperature was lowered and the modified prepolymer was discharged.

[0076] Solvent, modified prepolymer, and 1 / 3 of the initiator were added to a four-necked flask. Nitrogen gas was introduced and the flask was heated. Methyl methacrylate, isoborneol methacrylate, isooctyl acrylate, and the remaining initiator were mixed evenly to form a mixture, which was then placed in a feeding funnel. When the solvent refluxed, 10% of the mixture was added dropwise to the four-necked flask over 15 minutes. The temperature was then raised to 142°C, and the remaining mixture was added dropwise at a uniform rate over 4 hours while maintaining the temperature. The mixture was stirred and kept at the temperature for 4 hours. After cooling and filtration, the hydroxyl-containing acrylic resin was obtained.

[0077] Example

[0078] Example 1

[0079] A DTF white ink heat transfer film with surface texture, as shown in the reference. Figure 1 It includes a PET base film layer 1, a release layer 2 and an ink-absorbing coating layer 3 stacked in sequence. The PET base film layer 1 has a UV-cured surface texture. The release layer 2 is coated with a release agent and the ink-absorbing coating layer 3 is coated with an ink-absorbing paint.

[0080] A 75μm PET film is selected as the base film layer, and surface textures are created on the PET film using UV curing texturing technology. Surface textures can include raster patterns, cat's eye patterns, water droplet patterns, brushed patterns, etc. The specific preparation method can be referenced as follows: Select a suitable mold, form a texture by chemically etching a metal plate to obtain an etched mold; clean the surface of the PET film, or, if necessary, perform corona treatment to increase surface energy; apply UV adhesive to the PET surface by roller coating or drop application, then cover the mold with the UV adhesive-coated PET film, and apply pressure to allow the UV adhesive to fill the mold texture; use a UV light source to irradiate and rapidly cure the UV adhesive, then peel the PET film off the mold, at which point the mold texture is replicated on the UV adhesive.

[0081] The release agent is coated onto the UV adhesive of the PET base film using an anilox roller coating method to obtain the release layer;

[0082] The ink-absorbing coating is applied to the release layer by a micro-grooved roller coating method to obtain the ink-absorbing coating layer. The PET base film layer, the release layer and the ink-absorbing coating layer together constitute the DTF white ink heat transfer film.

[0083] The release agent comprises the following raw materials in parts by weight:

[0084] 50 parts of hydroxyl-containing acrylic resin were purchased from Dongguan Delun New Materials Co., Ltd., model BASF Joncryl 587, CAS number 37956-57-3;

[0085] Nine parts of curing agent, a self-sealing isocyanate curing agent, purchased from Shanghai Zhenlishi Network Technology Co., Ltd., model VESTAGON B-1530;

[0086] 10 parts of fluorocarbon resin, selected from polytetrafluoroethylene resin, purchased from Dongguan Zhangmutou Hengtai Plastic Raw Material Business Department;

[0087] 4 parts of modified nano-silica;

[0088] One part of surfactant is selected from a mixture of stearic acid and Span 60 in a weight ratio of 60:40, specifically 0.6 parts stearic acid and 0.4 parts Span 60;

[0089] 8 parts toluene;

[0090] 9 parts of ethyl acetate;

[0091] The modified nano-silica is prepared by the following steps: 1g of nano-silica is poured into a flask, 10ml of concentrated nitric acid with a mass fraction of 68% is added, and the mixture is left to stand at room temperature for 10min. The nitric acid is poured out, leaving the acidified nano-silica in the flask. The mixture is heated for 1min to evaporate the nitric acid. Then, 20ml of anhydrous ethanol is added to the flask, and the mixture is heated under reflux at 95℃ for 20min using an electronic heating mantle to evaporate the ethanol, thus obtaining the modified nano-silica.

[0092] The ink-absorbing coating comprises the following raw materials in parts by weight:

[0093] 50 parts of polyvinyl alcohol;

[0094] 18 parts of waterborne polyurethane resin, purchased from Shanghai Bolino New Material Technology Co., Ltd., model PU-104;

[0095] 20 parts of fumed silica, purchased from Shanghai Zhenlishi Network Technology Co., Ltd., model Evonik AEROSILR8200; 3 parts of boric acid;

[0096] 0.3 parts of wetting and leveling agent were purchased from Chongqing Hongruichuan New Material Technology Co., Ltd., model BYK333.

[0097] Example 2

[0098] A DTF white ink heat transfer film with surface texture, as shown in the reference. Figure 1 It includes a PET base film layer 1, a release layer 2 and an ink-absorbing coating layer 3 stacked in sequence. The PET base film layer 1 has a UV-cured surface texture. The release layer 2 is coated with a release agent and the ink-absorbing coating layer 3 is coated with an ink-absorbing paint.

[0099] The release agent comprises the following raw materials in parts by weight:

[0100] 80 parts of hydroxyl-containing acrylic resin were purchased from Guangzhou Siteyuan Chemical Co., Ltd., model Hypomer FS-4080F;

[0101] 17 parts of curing agent, melamine curing agent, purchased from Guangzhou Qian'an Chemical Co., Ltd., model EHP4700S;

[0102] 18 parts of fluorocarbon resin, selected from polyvinylidene fluoride resin, purchased from Guangzhou Hongcheng Plastics Co., Ltd., brand name French Arkema 2500-20;

[0103] 7 parts of modified nano-silica;

[0104] Three parts of surfactant were selected, which was a mixture of stearic acid and Span 60 in a weight ratio of 70:30, specifically 2.1 parts stearic acid and 0.9 parts Span 60.

[0105] 13 parts of toluene;

[0106] 16 parts of ethyl acetate;

[0107] The modified nano-silica is prepared by the following steps: 1g of nano-silica is poured into a flask, 15ml of concentrated nitric acid with a mass fraction of 68% is added, and the mixture is allowed to stand at room temperature for 20min. The nitric acid is poured out, leaving the acidified nano-silica in the flask. The mixture is heated for 2min to evaporate the nitric acid. Then, 30ml of anhydrous ethanol is added to the flask, and the mixture is heated under reflux at 100℃ for 30min using an electronic heating mantle to evaporate the ethanol, thus obtaining the modified nano-silica.

[0108] The ink-absorbing coating comprises the following raw materials in parts by weight:

[0109] 65 parts of polyvinyl alcohol;

[0110] 27 parts of waterborne polyurethane resin, purchased from Shanghai Bolino New Material Technology Co., Ltd., model PU-104;

[0111] 38 parts of fumed silica, purchased from Shanghai Zhenlishi Network Technology Co., Ltd., model Evonik AEROSILR8200; 5 parts of boric acid;

[0112] 0.8 parts of wetting and leveling agent were purchased from Chongqing Hongruichuan New Material Technology Co., Ltd., model BYK333.

[0113] Example 3

[0114] A DTF white ink heat transfer film with surface texture, as shown in the reference. Figure 1 It includes a PET base film layer 1, a release layer 2 and an ink-absorbing coating layer 3 stacked in sequence. The PET base film layer 1 has a UV-cured surface texture. The release layer 2 is coated with a release agent and the ink-absorbing coating layer 3 is coated with an ink-absorbing paint.

[0115] The release agent comprises the following raw materials in parts by weight:

[0116] 70 parts of hydroxyl-containing acrylic resin were purchased from Dongguan Delun New Materials Co., Ltd., model BASF Joncryl 587, CAS number 37956-57-3;

[0117] 13 parts of curing agent, melamine curing agent, purchased from Guangzhou Qian'an Chemical Co., Ltd., model EHP4700S;

[0118] 14 parts of fluorocarbon resin, selected from a mixture of 8 parts polytetrafluoroethylene resin and 6 parts polyvinylidene fluoride resin;

[0119] 6 parts of modified nano-silica;

[0120] Two parts of surfactant were selected, which were a mixture of stearic acid and Span 60 in a weight ratio of 65:35, specifically 1.3 parts stearic acid and 0.7 parts Span 60.

[0121] 11 parts of toluene;

[0122] 14 parts of ethyl acetate;

[0123] The modified nano-silica is prepared by the following steps: 1g of nano-silica is poured into a flask, 13ml of concentrated nitric acid with a mass fraction of 68% is added, and the mixture is left to stand at room temperature for 15min. The nitric acid is poured out, leaving the acidified nano-silica in the flask. The mixture is heated for 1min to evaporate the nitric acid. Then, 25ml of anhydrous ethanol is added to the flask, and the mixture is heated under reflux at 95℃ for 25min using an electronic heating mantle to evaporate the ethanol, thus obtaining the modified nano-silica.

[0124] The ink-absorbing coating comprises the following raw materials in parts by weight:

[0125] 58 parts of polyvinyl alcohol;

[0126] 22 parts of waterborne polyurethane resin, purchased from Shanghai Bolino New Material Technology Co., Ltd., model PU-104;

[0127] 28 parts of fumed silica, purchased from Shanghai Zhenlishi Network Technology Co., Ltd., model Evonik AEROSILR8200; 4 parts of boric acid;

[0128] 0.6 parts of wetting and leveling agent were purchased from Chongqing Hongruichuan New Material Technology Co., Ltd., model BYK333.

[0129] Example 4

[0130] The difference between this embodiment and Embodiment 1 is that the release layer of the DTF white ink heat transfer film is different, specifically the hydroxyl-containing acrylic resin in the release agent raw material is different.

[0131] In this embodiment, the hydroxyl-containing acrylic resin is the hydroxyl-containing acrylic resin obtained in Preparation Example 1.

[0132] Example 5

[0133] The difference between this embodiment and Embodiment 1 is that the release layer of the DTF white ink heat transfer film is different, specifically the hydroxyl-containing acrylic resin in the release agent raw material is different.

[0134] In this embodiment, the hydroxyl-containing acrylic resin used is the hydroxyl-containing acrylic resin obtained in Preparation Example 2.

[0135] Comparative Example

[0136] Comparative Example 1

[0137] The difference between this comparative example and Example 1 is that the release layer of the DTF white ink heat transfer film is different. Specifically, in the release agent raw materials of this comparative example, an equal mass of nano-silica is used instead of modified nano-silica.

[0138] Comparative Example 2

[0139] The difference between this comparative example and Example 1 is that the release layer of the DTF white ink heat transfer film is different. Specifically, in the release agent raw materials of this comparative example, an equal mass of hydroxyl-containing acrylic resin is used instead of fluorocarbon resin.

[0140] Performance testing

[0141] The release agents and DTF white ink heat transfer films prepared in Examples 1-5 and Comparative Examples 1-2 were tested for the following properties, and the results are summarized in Table 1.

[0142] Surface tension of release agent: The surface tension of release agent was measured using a JK99B fully automatic tension meter; Release force of release layer: Release coating was applied to PET base film to form release layer, and after bonding with Nitto 31B tape for 20 minutes, tensile test was performed (force value detected at a peeling speed of 300 mm / min at a 180° angle);

[0143] Cold and hot tear test of white ink heat transfer film for transfer: Pre-set test patterns were printed on the DTF white ink heat transfer films prepared in Examples 1-5 and Comparative Examples 1-2, and powder (hot melt TPU powder) was shaken off on the patterns. After baking at high temperature to fix the color, the films were transferred to a heat transfer machine. The temperature was set at 165 degrees Celsius and the time was 8 seconds. Hand tearing was performed at room temperature (20°C) and high temperature (150°C) to evaluate the peeling effect of the heat transfer film, with the premise of not damaging the effect of the transferred pattern.

[0144] Table 1

[0145]

[0146] According to the data in Table 1, the DTF white ink heat transfer film prepared in this application has surface textures made on the PET base film layer. The textures are printed onto the release layer. When the heat transfer film is transferred and peeled off, the resulting pattern will have surface textures as the release layer is peeled off.

[0147] The release layer prepared by the DTF white ink heat transfer film in this application has a light release force, produces less noise when peeling from the PET base film, and can be peeled off successfully by both cold and hot methods. The transferred pattern is clear, with complete edges, and the transfer effect is excellent. The release layer has moderate surface tension, enabling it to spread and wet the PET base film, and peeling is easier while maintaining good and stable adhesion to the PET base film.

[0148] Compared to Example 1, Examples 4-5 use acrylic resin modified with glycidyl tert-carbonate as the raw material for the release agent. The surface tension and release force are further reduced compared to Example 1, resulting in better hot-tear effect compared to Example 1.

[0149] Compared to Example 1, Comparative Example 1 used unmodified nano-silica as the raw material for the release agent. Because nano-silica cannot disperse well in hydroxyl-containing acrylic and fluorocarbon resin systems, it easily agglomerates, resulting in poor stability of the release agent. Furthermore, nano-silica has a higher surface tension, leading to greater adhesion between the release agent and the PET base film layer. Compared to Example 1, it is not as easy to peel off the release layer during transfer, resulting in a greater release force.

[0150] Compared to Example 1, Comparative Example 2 did not include fluorocarbon resin in the release agent raw materials. Fluorocarbon resin itself has extremely low surface tension and good weather resistance and high temperature resistance. The combination of fluorocarbon resin and hydroxyl-containing acrylic resin can better regulate the surface tension of the release agent. When fluorocarbon resin was not added, the surface tension of the release agent increased, the release force increased, resulting in difficulty in peeling off the release layer and unclear pattern edges.

[0151] 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 DTF white ink heat transfer film with surface texture, characterized in that: The material comprises a PET base film layer, a release layer, and an ink-absorbing coating layer stacked sequentially. The PET base film layer has a UV-curable surface texture. The release layer is coated with a release agent, and the ink-absorbing coating layer is coated with an ink-absorbing paint. The release agent comprises the following raw materials in parts by weight: 50-80 parts of hydroxyl-containing acrylic resin; 9-17 parts of curing agent; 10-18 parts of fluorocarbon resin; 4-7 parts of modified nano-silica; 1-3 parts surfactant; 8-13 parts of toluene; 9-16 parts of ethyl acetate; The modified nano-silica is prepared by the following steps: pouring nano-silica into a flask, adding concentrated nitric acid, and letting it stand at room temperature for 10-20 minutes. Pour out the nitric acid, leaving acidified nano-silica in the flask. Heat for 1-2 minutes to evaporate the nitric acid. Then add anhydrous ethanol to the flask and heat under reflux at 95-100℃ for 20-30 minutes using an electronic heating mantle to evaporate the ethanol, thereby obtaining modified nano-silica. The ratio of concentrated nitric acid volume (mL): anhydrous ethanol volume (mL): nano-silica mass (g) is 10-15:20-30:

1.

2. The DTF white ink heat transfer film with surface texture according to claim 1, characterized in that: The hydroxyl-containing acrylic resin comprises the following raw materials in parts by weight: 10-15 parts of methyl methacrylate; 8-12 parts of isobornyl methacrylate; 25-40 parts of isooctyl acrylate; 1-2 parts of 2-mercaptopropionic acid; 13-27 parts of modified prepolymer; 2-5 parts of initiator; Solvent 25-35 parts; The modified prepolymer is a modified prepolymer synthesized from acrylic acid and glycidyl tert-carbonate.

3. The DTF white ink heat transfer film with surface texture according to claim 2, characterized in that: The modified prepolymer is prepared by the following steps: Add 60-70 parts by weight of glycidyl tert-carbonate, 0.05-0.2 parts by weight of stannous octoate, and 0.4-0.8 parts by weight of antioxidant to a three-necked flask, purge with nitrogen and heat to 80-85°C, then add dropwise a mixture of 20-30 parts by weight of acrylic acid and 0.01-0.05 parts by weight of polymerization inhibitor over 15-20 minutes. Maintain the reaction at 90-95°C for 2 hours, and when the acid value is ≤12 mg KOH / g, cool down and discharge to obtain the modified prepolymer.

4. The DTF white ink heat transfer film with surface texture according to claim 1, characterized in that: Fluorocarbon resin is one or more of polytetrafluoroethylene, polyvinylidene fluoride, and fluoroolefin-vinyl ether copolymer.

5. A DTF white ink heat transfer film with surface texture according to claim 1, characterized in that: The curing agent is selected from one or both of melamine-based curing agents and isocyanate-based curing agents.

6. A DTF white ink heat transfer film with surface texture according to claim 1, characterized in that: The surfactant is a mixture of stearic acid and Span 60 in a weight ratio of 60-70:40-30.

7. A DTF white ink heat transfer film with surface texture according to claim 1, characterized in that: The ink-absorbing coating comprises the following raw materials in parts by weight: 50-65 parts polyvinyl alcohol; 18-27 parts waterborne polyurethane resin; 20-38 parts fumed silica; and 3-5 parts boric acid. 0.3-0.8 parts of wetting and leveling agent.

8. A DTF white ink heat transfer film with surface texture according to claim 2, characterized in that: The initiator is selected from one or both of tert-butyl peroxide benzoate and tert-butyl peroxide acetate.

9. A DTF white ink heat transfer film with surface texture according to claim 2, characterized in that: The hydroxyl-containing acrylic resin is prepared by the following steps: In a four-necked flask, add solvent, modified prepolymer, and 1 / 3 of the initiator. Purge with nitrogen and heat to a uniform temperature. Mix methyl methacrylate, isobornyl methacrylate, isooctyl acrylate, and the remaining initiator to form a homogeneous mixture and place it in a feeding funnel. When the solvent refluxes, add 10% of the mixture dropwise to the four-necked flask over 10-15 minutes. Continue heating to 137-142°C and, while maintaining the temperature, add the remaining mixture dropwise at a uniform rate over 3.5-4 hours. Stir and maintain the temperature for 3-4 hours. Cool and filter to obtain hydroxyl-containing acrylic resin.

10. A DTF white ink heat transfer film with surface texture according to claim 1, characterized in that, The DTF white ink heat transfer film is prepared through the following steps: Surface textures are created on PET film using UV curing texturing technology to obtain a PET base film layer; A release layer is obtained by applying a release agent onto a PET base film using an anilox roller coating method. An ink-absorbing coating is obtained by applying an ink-absorbing coating material onto the release layer using a micro-concave roller coating method, forming a DTF white ink heat transfer film.

Images