A method for preparing a printed pattern having a three-dimensional structure

Abstract

The application provides a preparation method of a printed product with a three-dimensional structure, and relates to the technical field of printing. In the mold pressing mold, the combined parts are fixed by magnetic attraction, the inner cavity of the combined parts is matched with the outer shape structure of the printed product, when the mold pressing foaming is performed, the coating is expanded and the printed product is formed, then the magnetic attraction is released and the combined parts are disassembled, and the printed product can be obtained. The preparation method of the printed product can be applied to the printed product with a relatively complex structure, and solves the problem that the preparation process of the current foaming printed product is not suitable for preparing the printed product with a complex structure.

Description

Technical Field

[0001] This invention belongs to the field of printing technology and relates to a method for preparing a print with a three-dimensional structure. Background Technology

[0002] Printing is a common decorative and protective material in the textile industry. Printing generally involves applying a printing paste to textile fabric. Due to gravity and the fluidity of the paste, printed patterns typically widen from top to bottom. With increasing consumer demand, more requirements are being placed on the shapes of printed patterns, especially various three-dimensional shapes, such as spirals, patterns that widen in the middle, and even more complex three-dimensional structures.

[0003] Current printing processes cannot meet the requirements for the new printing shapes mentioned above. Although 3D printing technology can provide printing of various complex shapes, it is costly, time-consuming, and unsuitable for water-based printing pastes commonly used in current printing processes, such as water-based polyurethane pastes.

[0004] Foam printing can be made into various three-dimensional shapes through molding dies. However, for some foam printing with more complex structures (especially those with a local structure that is wider at the top and narrower at the bottom), the printing may be damaged or destroyed when the molding die is removed.

[0005] Therefore, the foam printing process urgently needs further improvement. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a method for preparing a print with a three-dimensional structure.

[0007] The technical solution of the present invention is as follows:

[0008] A method for preparing a print with a three-dimensional structure, comprising the following steps: S1. Provide a detachable assembly, the assembly being composed of a plurality of parts, at least one of the plurality of parts having magnetic attraction properties; The combined components are magnetically fixed to the inner cavity of the molding die to form a composite mold; the inner cavity of the composite mold matches the shape of the target print. S2. Apply the water-based foaming slurry to the preset position on the fabric, allow it to dry slightly, and obtain a rough coating. S3. The composite mold is placed on the coarse coating and covers the coarse coating. The coarse coating is heated, molded, and foamed, then cooled to separate the molding mold from the combined component. The combined component is then disassembled to obtain the print with a three-dimensional structure.

[0009] Preferably, the surface energy of the inner surface of the combined component in contact with the printing in step S1 does not exceed 27 mN / m at 25°C.

[0010] Preferably, the material of the part in step S1 is selected from one or more of silicone rubber, silicone resin, fluororubber, fluoroplastics and iron materials.

[0011] More preferably, when the material of the part is selected from silicone rubber, silicone resin, fluororubber and / or fluoroplastic, the part contains iron powder and / or iron oxide powder. When the material of the part is selected from ferrous materials, the inner surface of the part is coated with a coating composed of organosilicon materials and / or organofluorine materials.

[0012] Preferably, in step S1, the combined components are magnetically fixed to the inner cavity of the molding die after assembly, which means that the combined components and the molding die have a magnetic attraction effect, or the combined components are fixed to the inner cavity of the molding die by external magnetic force.

[0013] Preferably, the water-based foaming slurry in step S2 is selected from water-based polyurethane foaming slurry; The surface drying temperature shall not exceed 70°C.

[0014] More preferably, the waterborne polyurethane foaming slurry, by weight, comprises the following raw materials: 80-90% waterborne polyurethane dispersion, 0.2-0.5% pH adjuster, 2-5% foaming agent, 0.4-0.6% dispersant, 3-6% slow-drying agent, 0.2-1% thickener, 0.3-0.6% defoamer, 2-5% crosslinking agent, with the balance being water.

[0015] Preferably, the conditions for heating and molding foaming in step S3 are: temperature 140-160℃, pressure 0.3-1MPa, and foaming time 40-70s.

[0016] Preferably, in step S3, separating the molding die from the assembly is achieved by using a magnetic release device to remove the magnetic attraction or withdraw the external magnetic force.

[0017] Preferably, at least some parts of the printed area in step S3 have a structure that is wider at the top and narrower at the bottom or protrudes laterally.

[0018] The beneficial effects of this invention are as follows: This invention uses detachable modular components as the molding die during printing molding and foaming. The modular components are magnetically attached to the molding die. After molding and foaming, the magnetic attachment is released, and the modular components are disassembled to obtain the printed product. The preparation method of this invention is suitable for printing of various shapes and structures, has wide applicability, and can prepare printing of various complex shapes and structures, such as printing with a spiral structure. Attached Figure Description

[0019] Figure 1 This is a photograph of the printed product obtained in Example 1.

[0020] Figure 2 This is a photograph of the printed product obtained in Example 2. Detailed Implementation

[0021] The technical solution of the present invention will be further explained and described below through specific embodiments.

[0022] This invention proposes a method for preparing a print with a three-dimensional structure, the steps of which include: S1. Provides a detachable assembly, which is composed of several parts, at least one of which has magnetic attraction properties; The combined components are magnetically fixed to the inner cavity of the molding die to form a composite mold; the inner cavity of the composite mold matches the shape of the target print. S2. Apply the water-based foaming slurry to the preset position on the fabric, allow it to dry slightly, and obtain a rough coating. S3. The composite mold is placed on the coarse coating and covered with the coarse coating. The coarse coating is heated, molded, and foamed. After cooling, the molding mold is separated from the combined components. The combined components are then disassembled to obtain a print with a three-dimensional structure.

[0023] This invention uses detachable modular components as the mold for compression molding and foaming. After the printing foam is formed, the mold is separated and the modular components are disassembled to obtain the printed image. Therefore, the preparation method of this invention is suitable for printing of various shapes and structures, even some complex structures, such as spiral structures. It only requires designing the inner cavity of the modular components to match the shape of the printed image. The modular components can be composed of several parts, such as two or three parts, which can be assembled and fixed by splicing, snap-fitting, or plugging. When in use, the modular components of this invention are installed in the inner cavity of the mold and fixed by magnetic attraction. After molding is completed, the magnetic attraction is released to separate the modular components from the mold. Moreover, the detachable modular components can be disassembled and assembled multiple times, resulting in high reusability.

[0024] In some embodiments, the surface energy of the inner surface of the assembled component in contact with the printing in step S1 does not exceed 27 mN / m at 25°C. Low surface energy of the inner surface of the assembled component facilitates demolding after molding, avoiding problems such as print damage caused by unsuccessful demolding.

[0025] In some embodiments, the material of the part in step S1 is selected from one or more of silicone rubber, silicone resin, fluororubber, fluoroplastics, and ferrous materials. Silicone rubber, silicone resin, fluororubber, and fluoroplastics have low surface energy but do not have magnetic properties. Therefore, when the material of the part is selected from silicone rubber, silicone resin, fluororubber, and / or fluoroplastics, the part contains iron powder and / or magnetite powder, which can give the part magnetic properties. Ferrous materials possess magnetic properties but also have high surface energy. Therefore, when a part is made of ferrous material, its inner surface is coated with a coating composed of silicone and / or fluorine materials. For example, the silicone material can be silicone rubber or silicone resin, and the fluorine material can be polytetrafluoroethylene, fluorosilane coupling agents, fluoroether silane coupling agents, etc. There are no particular limitations on the coating thickness; 5-100 μm is acceptable.

[0026] In some embodiments, in step S1, the assembled components are magnetically fixed to the inner cavity of the molding die. This means that a magnetic attraction is formed between the assembled components and the molding die, or the assembled components are fixed to the inner cavity of the molding die by external magnetic force. The magnetic fixation of the assembled components to the molding die allows for convenient installation and separation, and also utilizes the characteristics of the molding die to achieve foaming and molding of the printed coating. When a magnetic attraction is formed between the assembled components and the molding die, for example, if the material of the part contains iron oxide (Fe3O4), the part has magnetic attraction capabilities. When the molding die is made of iron, a magnetic attraction can occur between the part and the molding die. When the assembled components are fixed to the inner cavity of the molding die by external magnetic force, for example, if the assembled components contain iron materials or are made of silicone rubber but contain iron powder, a magnet can be placed on the outside of the molding die. The magnet attracts the assembled components, and the assembled components are fixed inside the molding die.

[0027] In some embodiments, the aqueous foaming slurry in step S2 is selected from aqueous polyurethane foaming slurry; The surface temperature should not exceed 70℃.

[0028] Waterborne polyurethane paste is a commonly used waterborne foaming paste, and the resulting prints have good flexibility and a good hand feel. The surface drying temperature should not exceed 70℃ to avoid foaming during surface drying.

[0029] In some embodiments, the waterborne polyurethane foam slurry, by weight, comprises: 80-90% waterborne polyurethane dispersion, 0.2-0.5% pH adjuster, 2-5% foaming agent, 0.4-0.6% dispersant, 3-6% slow-drying agent, 0.2-1% thickener, 0.3-0.6% defoamer, 2-5% crosslinking agent, with the balance being water. The aforementioned waterborne polyurethane foam slurry is relatively mature. The foaming agent can be a thermally expanding microsphere foaming agent, an organic chemical thermal decomposition foaming agent, etc., all of which are readily available on the market. Different color powders or color pastes can also be added to the aforementioned waterborne polyurethane foam slurry according to color requirements.

[0030] In some embodiments, the conditions for heating and molding foaming in step S3 are: temperature 140-160℃, pressure 0.3-1MPa, and foaming time 40-70s. After the coarse coating is molded and foamed, it will form an external shape that matches the internal cavity structure due to the internal cavity structure of the assembled component (i.e., the internal cavity structure of the composite mold).

[0031] In some embodiments, separating the molding die from the assembled component in step S3 involves using a magnetic release device to remove the magnetic attraction or external magnetic force. When a magnetic attraction forms between the assembled component and the molding die, the assembled component is attracted and fixed in the molding die by magnetic force. When it is necessary to release the magnetic attraction, the magnetic release device cancels the magnetic force through methods such as electrically controlled reverse magnetic field, mechanical pushing, magnetic pole reversal, or external magnetic key, thereby achieving rapid separation and release of the assembled component. In this invention, the magnetic release device can be located inside or outside the molding die, as long as it can effectively release the magnetic attraction. When the assembled component is fixed in the cavity of the molding die by external magnetic force, removing the external magnetic force, such as a magnet, can separate the assembled component from the molding die.

[0032] In some embodiments, at least a localized portion of the printed area in step S3 exhibits a distinct top-wide, bottom-narrow or laterally convex structure. The printing process of this invention is suitable for various complex structures, especially those difficult to demold from the molding die, such as printed structures with a distinct top-wide, bottom-narrow or laterally convex structure, like three-dimensional printing with a spiral structure.

[0033] The technical solution of the present invention will be further described and illustrated below with reference to various embodiments. Unless otherwise specified, the parts mentioned in the following embodiments are parts by weight.

[0034] Example 1 The waterborne polyurethane foaming slurry, by weight, consists of the following raw materials: 80% waterborne polyurethane dispersion (solid content 55wt%), 0.3% AMP-95, 4% thermally expandable microspheres Expansionl 043DU80, 0.5% dispersant BYK194, 3% slow-drying agent propylene glycol, 0.8% polyurethane associative thickener, 0.4% dimethyl defoamer, 4% waterborne isocyanate crosslinking agent, 3% silver colorant, and the balance being water.

[0035] The detachable assembly consists of three parts that are connected and fixed together by plugging in. All parts are made of polytetrafluoroethylene (PTFE) (surface energy 19.1 mN / m) and contain iron(III) oxide, giving them magnetic properties. The internal cavity of the assembly formed by the three parts has a certain spiral structure.

[0036] The combined components are magnetically fixed to the inner cavity of the molding die to form a composite mold; the inner cavity of the composite mold is the inner cavity of the combined components.

[0037] The above-mentioned water-based foaming paste was applied to the designated pattern position on the shoe upper fabric by rotary screen printing. After printing, it was baked at 60°C until surface dry to obtain a rough coating. The composite mold is placed on top of the coarse coating and covered with the coarse coating. The coarse coating is heated and molded to foam at a temperature of 140℃ and a pressure of 0.5MPa for 50s. Then it is allowed to cool naturally. The magnetic attraction between the molding mold and the assembly is released by a magnetic release device, and the molding mold and the assembly are separated. The assembly is then disassembled to obtain a print with a three-dimensional structure.

[0038] The actual product image of the print in this embodiment is attached. Figure 1 As shown, it has a distinct spiral structure, with the upper part of the printed portion protruding laterally relative to the lower part.

[0039] Example 2 The waterborne polyurethane foaming slurry, by weight, consists of the following raw materials: 80% waterborne polyurethane dispersion (solid content 55wt%), 0.5% AMP-95, 5% thermally expandable microspheres Expansionl 043DU80, 0.6% dispersant BYK194, 3% slow-drying agent propylene glycol, 0.5% polyurethane associative thickener, 0.4% dimethyl defoamer, 5% waterborne isocyanate crosslinking agent, 3% silver pigment, and the balance being water.

[0040] The detachable assembly is composed of four parts that are spliced ​​and fixed together, all of which are made of iron. The inner cavity of the assembly formed by the four parts is the same in shape and size as the inner cavity of the assembly in Example 1, and the inner cavity is coated with a silicone resin coating with a thickness of 20μm and a surface energy of 26mN / m.

[0041] The combined components are magnetically fixed to the inner cavity of the molding die by magnets placed on the outside of the molding die, forming a composite mold; the inner cavity of the composite mold is the inner cavity of the combined components.

[0042] The above-mentioned water-based foaming paste was applied to the designated pattern position on the shoe upper fabric by rotary screen printing. After printing, it was baked at 65°C until surface dry to obtain a rough coating. The composite mold is placed on top of the coarse coating and covered with the coarse coating. The coarse coating is heated and molded to foam at a temperature of 140℃ and a pressure of 0.3MPa for 65s. Then it is allowed to cool naturally. The magnetic attraction between the molding mold and the assembly is released by a magnetic release device, and the molding mold and the assembly are separated. The assembly is then disassembled to obtain a print with a three-dimensional structure.

[0043] The printing in this embodiment also has a distinct spiral structure and is basically the same in shape as the printing in Embodiment 1, as shown in the attached figure. Figure 2 As shown.

[0044] As described above, the basic principles, main features, and advantages of the present invention have been shown and described. Those skilled in the art should understand that the present invention is not limited to the above embodiments, which are merely preferred embodiments and should not be construed as limiting the scope of the invention. All equivalent changes and modifications made in accordance with the scope of the patent and the description should still fall within the scope of the present invention. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a print with a three-dimensional structure, characterized in that the steps include... include: S1. Provide a detachable assembly, the assembly being composed of a plurality of parts, at least one of the plurality of parts having magnetic attraction properties; The combined components are magnetically fixed to the inner cavity of the molding die to form a composite mold; The inner cavity of the composite mold matches the shape of the target print; S2. Apply the water-based foaming slurry to the preset position on the fabric, allow it to dry slightly, and obtain a rough coating. S3. The composite mold is placed on the coarse coating and covers the coarse coating. The coarse coating is heated, molded, and foamed, then cooled to separate the molding mold from the combined component. The combined component is then disassembled to obtain the print with a three-dimensional structure.

2. The method for preparing a three-dimensional printed pattern according to claim 1, characterized in that, The surface energy of the inner surface of the combined component in contact with the printing in step S1 does not exceed 27 mN / m at 25°C.

3. The method for preparing a three-dimensional printed pattern according to claim 1, characterized in that, The material of the part mentioned in step S1 is selected from one or more of silicone rubber, silicone resin, fluororubber, fluoroplastics and iron materials.

4. The method for preparing a print with a three-dimensional structure according to claim 3, characterized in that, When the material of the part is selected from silicone rubber, silicone resin, fluororubber and / or fluoroplastic, the part contains iron powder and / or iron oxide powder. When the material of the part is selected from ferrous materials, the inner surface of the part is coated with a coating composed of organosilicon materials and / or organofluorine materials.

5. The method for preparing a print with a three-dimensional structure according to claim 1, characterized in that, In step S1, the combined components are magnetically fixed to the inner cavity of the molding die after assembly. This creates a magnetic attraction between the combined components and the molding die, or the combined components are fixed to the inner cavity of the molding die by external magnetic force.

6. The method for preparing a print with a three-dimensional structure according to claim 1, characterized in that, The water-based foaming slurry mentioned in step S2 is selected from water-based polyurethane foaming slurry; The surface drying temperature shall not exceed 70°C.

7. The method for preparing a print with a three-dimensional structure according to claim 6, characterized in that, The waterborne polyurethane foaming slurry, by weight, comprises the following raw materials: 80-90% waterborne polyurethane dispersion, 0.2-0.5% pH adjuster, 2-5% foaming agent, 0.4-0.6% dispersant, 3-6% slow-drying agent, 0.2-1% thickener, 0.3-0.6% defoamer, 2-5% crosslinking agent, with the balance being water.

8. The method for preparing a print with a three-dimensional structure according to claim 1, characterized in that, The conditions for heating, molding, and foaming in step S3 are: temperature 140-160℃, pressure 0.3-1MPa, and foaming time 40-70s.

9. The method for preparing a three-dimensional printed pattern according to claim 1, characterized in that, In step S3, separating the molding die from the assembly component is achieved by using a magnetic release device or removing the external magnetic force to remove the magnetic attraction.

10. The method for preparing a print with a three-dimensional structure according to claim 1, characterized in that, In step S3, at least some parts of the printed area have a structure that is wider at the top and narrower at the bottom or protrudes laterally.

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