Wood grain transfer film and method of making and substrate

Abstract

The application relates to the field of heat transfer printing, discloses a wood grain transfer film and a preparation method and a printing substrate, the wood grain transfer film comprises, from bottom to top, a substrate layer, a release layer and a UV pattern layer; the UV pattern layer is printed by UV coating. The wood grain transfer film has the advantages that the UV pattern layer is printed by a gravure printing machine through UV coating, the wood grain pattern has a convex wood grain touch without adding fillers, the wear resistance of the UV pattern layer is improved, and the probability of wear is reduced when the wood grain transfer film is rubbed and collided by external objects.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heat transfer printing, and particularly relates to a wood grain transfer film, a preparation method and a printing substrate. BACKGROUND

[0002] The existing wood grain heat transfer printing film is widely used on aluminum alloy profiles such as anti-theft doors and windows. The main process flow is to first weld the aluminum profile into a shape, spray powder on the surface of the aluminum profile, and finally transfer the wood grain pattern on the surface of the aluminum profile by using the wood grain heat transfer printing film. The existing wood grain transfer pattern can simulate the three-dimensional effect of wood grain and also has 3D visual effect and convex wood grain texture. The applicant has developed a wood grain heat transfer printing film prepared by using heat sublimation transfer ink and fillers, so that the wood grain pattern has 3D visual effect and convex wood grain texture. Since the surface of such wood grain heat transfer printing film generally does not have a protective layer, during long-term use, the convex part of the wood grain pattern transferred on the surface of the aluminum profile is easily worn after being rubbed and collided by external objects, which affects the appearance of the product.

[0003] Therefore, the prior art still needs to be improved and developed. SUMMARY

[0004] In view of the above problems of the prior art, the present application aims to provide a wood grain transfer film, a preparation method and a printing substrate, and aims to solve the problem that the convex part of the existing wood grain pattern is easily worn.

[0005] The technical scheme of the present application is as follows:

[0006] A wood grain transfer film, wherein from bottom to top, the wood grain transfer film comprises a substrate layer, a release layer and a UV pattern layer in sequence; the UV pattern layer is printed by UV coating.

[0007] The wood grain transfer film, wherein the UV coating comprises the following raw materials in terms of weight fraction:

[0008] Hyperbranched tetrafunctional polyester acrylate 30-40 parts;

[0009] Fluorine-modified polyurethane acrylate 30-40 parts;

[0010] Epoxy resin 10-25 parts;

[0011] Nano-silicon dioxide 1-3 parts;

[0012] Initiator 2-3 parts;

[0013] Solvent 45-55 parts;

[0014] Pigment 0-20 parts.

[0015] The wood grain transfer film, wherein the substrate layer is a PVC film or a PET film.

[0016] The wood grain transfer film, wherein the solvent is a combination of ethyl acetate and butyl acetate.

[0017] The wood grain transfer film, wherein a mass ratio of the ethyl acetate to the butyl acetate is 1:1.

[0018] A method for preparing the wood grain transfer film, comprising the following steps:

[0019] The UV coating is prepared by mixing 30-40 parts of hyperbranched tetrafunctional polyester acrylate, 30-40 parts of fluorine-modified polyurethane acrylate, 10-25 parts of epoxy resin, 1-3 parts of nano-silicon dioxide, 2-3 parts of initiator, 45-55 parts of solvent, and 0-20 parts of pigment under light-proof conditions;

[0020] A release agent is brushed on the substrate layer, and the release layer is formed by drying at 110-130 DEG C;

[0021] The UV coating is printed on the side of the substrate layer coated with the release layer to form the UV pattern layer;

[0022] The finished product is rolled up, and the printing is completed.

[0023] The method for preparing the wood grain transfer film, wherein the process of printing the UV coating on the side of the substrate layer coated with the release layer to form the UV pattern layer specifically comprises the following steps:

[0024] According to the wood grain plate, a cylinder gravure roller engraved with a wood grain pattern is selected; the cylinder gravure roller is arranged on a gravure printing machine according to color sequences, and the UV coating of corresponding colors is poured into the cylinder gravure roller respectively; the viscosity of the UV coating is adjusted to be between 15 seconds and 30 seconds in a No. 3 cup, the temperature of the air bellow of the gravure printing machine is adjusted to be between 130 DEG C and 140 DEG C, and the production speed of the gravure printing machine is adjusted to be between 50 meters / minute and 200 meters / minute; the overprint printing is started, and the UV coating is printed on the side of the substrate layer coated with the release layer, dried, and formed into the UV pattern layer.

[0025] A printing substrate, wherein the wood grain transfer film is used for heat transfer printing on the printing substrate, and the UV pattern layer is attached to the printing substrate.

[0026] The printing substrate, wherein the printing substrate is an aluminum alloy profile, a stainless steel profile, or a steel plate.

[0027] Beneficial effects: the wood grain transfer film of the present application, the UV pattern layer is printed by UV paint through the gravure printing machine, by using UV paint, without adding fillers, the wood grain pattern can also have a convex wood grain feel, and the wear resistance of the UV pattern layer can also be improved, when rubbing and colliding with external objects, the probability of wear and tear is reduced. DETAILED DESCRIPTION

[0028] The present application provides a wood grain transfer film and a preparation method and a printing substrate. In order to make the purpose, technical scheme and effect of the present application more clear and explicit, the present application is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0029] The present application provides a wood grain transfer film, which comprises a substrate layer, a release layer and a UV pattern layer from bottom to top. The UV pattern layer is printed by UV paint.

[0030] The substrate layer can be a PVC film or a PET film. The UV pattern layer is printed by UV paint through the gravure printing machine. By using UV paint, without adding fillers, the wood grain pattern can also have a convex wood grain feel, and the wear resistance of the UV pattern layer can also be improved, when rubbing and colliding with external objects, the probability of wear and tear is reduced.

[0031] Further, the release layer is arranged between the UV pattern layer and the substrate layer. By arranging the release layer between the UV pattern layer and the substrate layer, the UV pattern layer and the substrate layer can be better separated during the transfer process. The release agent used to form the release layer is a commercially available product, which is not described here.

[0032] The UV paint used in the UV pattern layer can be a commercially available product. Since the existing wood grain transfer film is mainly used for aluminum alloy profiles such as security doors and windows, a part of it is used in outdoor environment, but the ordinary UV paint on the market will yellow after long-term sun and rain, which affects the appearance of the UV pattern layer. Therefore, the applicant has obtained a UV paint with yellowing resistance and wear resistance after many research and development experiments. Specifically, the UV paint comprises the following raw materials according to weight fraction:

[0033] Hyperbranched tetrafunctional polyester acrylate 30-40 parts;

[0034] Fluorine-modified polyurethane acrylate 30-40 parts;

[0035] Epoxy resin 10-25 parts;

[0036] Nano-silicon dioxide 1-3 parts;

[0037] Initiator 2-3 parts;

[0038] Solvent 45-55 parts;

[0039] Pigment 0-20 parts.

[0040] The hyperbranched tetrafunctional polyester acrylate is a resin with higher terminal group density and larger free volume, which interacts with the fluorine-modified polyurethane acrylate and nano-silica, can well improve the wear resistance of the UV pattern layer, and at the same time also makes the UV pattern layer have good flexibility, so that it can adapt to the winding and transportation of the heat transfer printing film in the production process. In addition, by adding epoxy resin, the anti-yellowing performance of the UV pattern layer can be well improved, so that it can better maintain the aesthetic appearance of the pattern ink layer. By adding pigments, UV coatings of different colors can be prepared to meet the color needs of the UV pattern layer. The UV pattern layer of the present application is printed by a gravure printing machine, and according to the shape of the three-dimensional wood grain pattern, the UV pattern layer is divided into multiple layers according to the color sequence and printed on the gravure printing machine according to the color sequence. The cylinder gravure roller is set according to the color sequence, and is printed in sequence according to the color sequence. One layer is printed, dried, and the next layer is printed. The parts of the convex wood grain are provided with more layers, so that they have the convex wood grain texture. In this way, the wood grain pattern with convex wood grain texture can be obtained without additional filler. Since no filler is used, the wear resistance of the wood grain pattern transferred to the surface of the aluminum profile is better, and even after rubbing and collision with external objects, it is not easy to be worn and can maintain a good appearance for a long time.

[0041] The raw materials used in the present application are all commercially available products. The hyperbranched tetrafunctional polyester acrylate, fluorine-modified polyurethane acrylate, epoxy resin, and initiator are purchased from Changxing Material, and the nano-silica is purchased from Yuechao Wear-resistant Material. The solvent can be a combination of ethyl acetate and butyl acetate, and the mass ratio of the two is 1:1.

[0042] The present application also provides a preparation method of the wood grain transfer film, which comprises the following steps:

[0043] Preparation of UV coating: mix 30-40 parts of hyperbranched tetrafunctional polyester acrylate, 30-40 parts of fluorine-modified polyurethane acrylate, 10-25 parts of epoxy resin, 1-3 parts of nano-silica, 2-3 parts of initiator, 45-55 parts of solvent, and 0-20 parts of pigment under light-proof conditions to obtain the UV coating;

[0044] Coating of release layer: brush the release agent on the substrate layer and dry at 110-130℃ to form the release layer;

[0045] Printing UV pattern layer: according to the wood grain plate, select the cylinder gravure roller engraved with wood grain pattern; set the cylinder gravure roller according to the color sequence on the gravure printing machine, respectively pour the corresponding color UV paint; adjust the viscosity of the UV paint to be between 15 seconds-30 seconds (3# cup), the air bellow temperature of the gravure printing machine to be between 130℃-140℃, and the production speed of the gravure printing machine to be between 50 meters / minute-200 meters / minute; start overprint printing, print the UV paint on the side of the substrate layer coated with the release layer, dry, and form the UV pattern layer;

[0046] Finished product winding, complete printing.

[0047] The wood grain transfer film prepared in the present application is in a solid state but not UV cured, and can be wound, stored, transported, etc. When transferring, the operation method is: brushing a layer of colorless or same color as the bottom color of the UV pattern layer UV paint on the surface of the metal printing substrate to wet the surface of the metal printing substrate, attaching the wood grain transfer film to the metal printing substrate, and performing UV light curing under the light energy of 600-900 mJ / cm 2 to form a cured UV pattern layer, and peeling off the substrate layer to complete the transfer process.

[0048] In the scheme of the present application, a printing substrate is also provided, and the printing substrate is attached with a UV pattern layer; the printing substrate is a metal printing substrate. The metal printing substrate can be an aluminum alloy profile, a stainless steel profile, a steel plate, etc.

[0049] The present application is further described below through specific examples.

[0050] Example 1

[0051] Configuring UV paint: mixing 35 parts of hyperbranched tetrafunctional polyester acrylate, 35 parts of fluorine-modified polyurethane acrylate, 18 parts of epoxy resin, 2 parts of nano silicon dioxide, 2.5 parts of initiator, 50 parts of solvent (ethyl acetate: butyl acetate = 1:1), and 10 parts of pigment under light-proof condition to obtain UV paint;

[0052] Coating release layer: brushing release agent on PVC film and drying at 120℃ to form release layer;

[0053] Printing UV pattern layer: according to the wood grain plate, select the cylinder gravure roller engraved with wood grain pattern; set the cylinder gravure roller according to the color sequence on the gravure printing machine, respectively pour the corresponding color UV paint; adjust the viscosity of the water-based ink to be between 20 seconds (3# cup), the air bellow temperature of the gravure printing machine to be between 135℃, and the production speed of the gravure printing machine to be between 180 meters / minute; start overprint printing, print the UV pattern layer on the side of the PVC film coated with the release layer, and dry;

[0054] Finished product winding, complete printing.

[0055] A layer of UV paint with the same color as the base color of the UV pattern layer is brushed on the surface of the metal printing object to wet the surface of the metal printing object. The wood grain transfer film is attached to the metal printing object, smoothed and attached. UV light curing is performed at 800 mJ / cm 2 The substrate layer is peeled off, and the heat transfer process is completed.

[0056] Performance testing is performed on the wood grain pattern on the surface of the aluminum alloy. The pencil hardness is 2H, the steel wool is rubbed back and forth 500 times under a force of 500 g without damage, and the yellowing value after irradiation under UV of 1 W / m for 200 h is 2.4.

[0057] Example 2

[0058] The UV paint is configured by mixing 31 parts of hyperbranched tetrafunctional polyester acrylate, 31 parts of fluorine-modified polyurethane acrylate, 12 parts of epoxy resin, 1.2 parts of nano silicon dioxide, 2.2 parts of initiator, 45 parts of solvent (ethyl acetate: butyl acetate = 1:1), and 5 parts of pigment under light-proof conditions to obtain the UV paint;

[0059] The release layer is coated by brushing the release agent on the PVC film and drying at 120°C to form the release layer;

[0060] The UV pattern layer is printed by selecting a cylinder gravure roller engraved with a wood grain pattern according to the wood grain plate. The cylinder gravure roller is set on the gravure printing machine according to the color sequence, and the corresponding color UV paint is poured into each cylinder gravure roller. The viscosity of the water-based ink is adjusted to be between 20 seconds (3# cup), the air bellow temperature of the gravure printing machine is adjusted to be between 135°C, and the production speed of the gravure printing machine is adjusted to be between 180 meters / minute. Start color registration printing, print the UV pattern layer on the side of the PVC film coated with the release layer, and dry;

[0061] The finished product is rolled up, and the printing is completed.

[0062] A layer of UV paint with the same color as the base color of the UV pattern layer is brushed on the surface of the metal printing object to wet the surface of the metal printing object. The wood grain transfer film is attached to the metal printing object, smoothed and attached. UV light curing is performed at 800 mJ / cm 2 The substrate layer is peeled off, and the heat transfer process is completed.

[0063] Performance testing is performed on the wood grain pattern on the surface of the aluminum alloy. The pencil hardness is 2H, the steel wool is rubbed back and forth 500 times under a force of 500 g without damage, and the yellowing value after irradiation under UV of 1 W / m for 200 h is 2.8.

[0064] Example 3

[0065] UV coating preparation: 40 parts of hyperbranched tetrafunctional polyester acrylate, 38 parts of fluorinated polyurethane acrylate, 25 parts of epoxy resin, 3 parts of nano silica, 3 parts of initiator, 55 parts of solvent (ethyl acetate: butyl acetate = 1:1), and 15 parts of pigment are mixed under light-protected conditions to obtain UV coating.

[0066] Applying release layer: Apply release agent to PVC film and dry at 120℃ to form release layer;

[0067] Printing the UV pattern layer: Select a cylindrical gravure roller with a wood grain pattern engraved on it according to the wood grain board; set the cylindrical gravure rollers on the gravure printing machine according to the color sequence, and pour in the corresponding UV coatings; adjust the viscosity of the water-based ink to between 20 seconds (cup No. 3), the air box temperature of the gravure printing machine to between 135℃, and the production speed of the gravure printing machine to between 180 meters / minute; start color printing, print the UV pattern layer on the side of the PVC film coated with the release layer, and dry;

[0068] The finished product is rolled up, and printing is complete.

[0069] Apply a layer of UV coating of the same color as the base color of the UV pattern layer to the surface of the metal substrate to wet the surface. Then, apply the wood grain transfer film onto the metal substrate, smoothing and adhering it. Apply the film at a light energy of 800 mJ / cm². 2 UV curing is performed to form a cured UV pattern layer. The substrate layer is then peeled off, completing the heat transfer process.

[0070] The wood grain pattern on the aluminum alloy surface was tested for performance. The pencil hardness was 2H. It was rubbed back and forth with steel wool 500 times under a force of 500g without damage. The yellowing value after 200h of UV irradiation at 1W / m was 2.2.

[0071] It should be understood that the application of this application is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of this application.

Claims

1. A wood grain transfer film characterized by, From bottom to top, it comprises a substrate layer, a release layer, and a UV pattern layer; the UV pattern layer is printed by UV coating; The UV coating is composed of the following raw materials in terms of weight fraction: Hyperbranched tetrafunctional polyester acrylate 30-40 parts; Fluorine-modified polyurethane acrylate 30-40 parts; Epoxy resin 10-25 parts; Nano-silicon dioxide 1-3 parts; Initiator 2-3 parts; Solvent 45-55 parts; Pigment 0-20 parts; The solvent is a combination of ethyl acetate and butyl acetate; The mass ratio of the ethyl acetate to the butyl acetate is 1:1; The preparation method of the wood grain transfer film comprises the following steps: Mixing hyperbranched tetrafunctional polyester acrylate 30-40 parts, fluorine-modified polyurethane acrylate 30-40 parts, epoxy resin 10-25 parts, nano-silicon dioxide 1-3 parts, initiator 2-3 parts, solvent 45-55 parts, and pigment 0-20 parts under light-proof conditions to obtain UV coating; Brushing the release agent on the substrate layer and drying at 110-130℃ to form the release layer; Printing the UV coating on the side of the substrate layer coated with the release layer to form the UV pattern layer; Rolling the finished product to complete printing; The process of printing the UV coating on the side of the substrate layer coated with the release layer to form the UV pattern layer specifically comprises the following steps: According to the wood grain board, a cylinder gravure roller engraved with a wood grain pattern is selected; the cylinder gravure roller is arranged on the gravure printing machine according to color sequence, and the corresponding color of the UV coating is poured into the cylinder gravure roller respectively; the viscosity of the UV coating is adjusted to be between 15 seconds and 30 seconds in a No. 3 cup, the air bellow temperature of the gravure printing machine is adjusted to be between 130℃ and 140℃, and the production speed of the gravure printing machine is adjusted to be between 50 meters / minute and 200 meters / minute; start overprint printing, print the UV coating on the side of the substrate layer coated with the release layer, dry, and form the UV pattern layer; According to the shape of the three-dimensional wood grain pattern, the UV pattern layer is divided into multiple layers according to color sequence, the cylinder gravure roller is arranged on the gravure printing machine according to color sequence, and printing is carried out according to color sequence, one layer is printed, dried, and the next layer is printed; After the wood grain transfer film is prepared, it is a solid but not UV-cured state; the convex wood grain part is provided with more layers.

2. The wood grain transfer film according to claim 1, wherein, The substrate layer is a PVC film or a PET film.

3. A printed substrate, characterized in that, The wood grain transfer film according to any one of claims 1-2 is used for heat transfer printing on a printing substrate, and the UV pattern layer is attached to the printing substrate.

4. The printed article of claim 3, wherein, The printing substrate is an aluminum alloy profile, a stainless steel profile, or a steel plate.