Preparation method of coating with suspended structure

Abstract

The invention relates to a preparation method of a coating with a suspended structure, which comprises the following steps: S1, placing a printing stock on a printing table, and enabling a telescopic end of a telescopic assembly to extend out and pass through a hollow printing position of a printing bottom plate in the horizontal direction; the telescopic end is arranged in the printing bottom plate; s2, after the slurry is printed and a wet film layer is obtained, the telescopic end retracts to the hollowed-out printing pattern position away from the printing bottom plate, the wet film layer is cured, and the coating with the suspended structure is obtained; and the viscosity of the slurry at the temperature of 23 DEG C is 170000-190000 cPs. A traditional screen printing technology is improved, the telescopic end capable of stretching out and retracting is additionally arranged in the printing bottom plate, the telescopic end stretches out and exceeds the hollowed-out printing pattern position of the bottom plate before printing, the telescopic end is wrapped by the wet film layer formed on the surface of a printing stock after slurry printing, and a hollow structure is formed on the wet film layer after the telescopic end retracts. And curing the wet film layer to form the coating with the suspended structure.

Description

Technical Field

[0001] The invention relates to the technical field of printing, and in particular to a method for preparing a coating with a suspended structure. Background Art

[0002] With the demand for personalized consumption, some special three-dimensional patterns with suspended effects are increasingly sought after in the clothing and shoe material markets. However, with traditional screen printing or hollow screen thick coating printing technology, the coating structure of the same pattern after printing is consistent from bottom to top or gradually decreases in area, and both cannot present a suspended effect.

[0003] 3D printing can achieve a suspended coating, but 3D printing is costly and inefficient, and cannot meet requirements in terms of cost and production efficiency.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for preparing a coating with a suspended structure.

[0006] The technical solution adopted by the present invention is:

[0007] The present invention provides a method for preparing a coating having a suspended structure, comprising the following steps:

[0008] S1. Place the substrate on the printing table, so that the telescopic end of the telescopic component extends and passes through the hollow printing position of the printing base plate in the horizontal direction;

[0009] The telescopic end is arranged in the printing base plate;

[0010] S2, after printing the slurry and obtaining a wet film layer, retracting the telescopic end to a hollow printing position away from the printing base plate, and curing the wet film layer to obtain the coating with a suspended structure;

[0011] The viscosity of the slurry at 23° C. is 170,000-190,000 cPs.

[0012] The present invention proposes a method for preparing a coating with a suspended structure, which improves the traditional screen printing process by adding a telescopic end that can be extended and retracted in the printing base plate, and the telescopic end extends and exceeds the hollow printing position of the base plate before printing. After the slurry is printed, the wet film layer formed on the surface of the substrate covers the telescopic end, and after the telescopic end is retracted, a hollow structure is formed in the wet film layer, and after the wet film layer is cured, a coating with a suspended structure is formed. The printing slurry of the present invention has a high viscosity and low fluidity, which is conducive to the molding effect and three-dimensional effect of the suspended structure coating, and the slurry of the present invention is not particularly limited, and can be a water-based slurry or an oily slurry, such as a solvent-based oily slurry or a UV-based oily slurry.

[0013] Preferably, the distance between the upper end of the telescopic end and the upper surface of the wet film layer is not less than 20% of the thickness of the wet film layer.

[0014] Preferably, the diameter of the telescopic end is 0.1-0.8 times the thickness of the wet film layer.

[0015] Preferably, the retraction speed of the telescopic end is not less than 2 m / s.

[0016] Preferably, the surface material of the telescopic end is selected from one of metal, inorganic non-metal, plastic, rubber and resin.

[0017] More preferably, the surface of the telescopic end is treated with hydrophobicity using organic groups.

[0018] More preferably, the organic group is selected from at least one of a C1-C18 hydrocarbon group, an organic silicon group and an organic fluorine group.

[0019] Preferably, the density of the slurry is not higher than 0.92 g / cm 3 .

[0020] Preferably, the slurry comprises: 6-10 wt% of hollow glass microspheres, 2-4 wt% of thermoplastic hollow polymer microspheres and 3-5 wt% of polyester fibers, or a combination of two or more thereof.

[0021] Preferably, the curing is selected from one of heating curing and UV light irradiation curing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the top view of the telescopic assembly in the extended state according to Embodiment 1 of the present invention;

[0023] Figure 2 is a cross-sectional schematic diagram of the telescopic assembly of Example 1 of the present invention in an extended state;

[0024] Figure 3This is a real-life rendering of a fabric with a suspended structure coating prepared in Example 1 of the present invention.

[0025] [Description of Reference Numerals]

[0026] 1. Screen frame; 2. Hollow printing position; 3. Telescopic end; 4. Bottom plate. DETAILED DESCRIPTION

[0027] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0028] The present invention provides a method for preparing a coating having a suspended structure, comprising the following steps:

[0029] S1. Place the substrate on the printing table, so that the telescopic end of the telescopic component extends and passes through the hollow printing position of the printing base plate in the horizontal direction;

[0030] The telescopic end is arranged in the printed base plate;

[0031] S2, after printing the slurry and obtaining a wet film layer, the telescopic end is retracted to a hollow printing position away from the printing base plate, and the wet film layer is cured to obtain a coating with a suspended structure;

[0032] The viscosity of the slurry at 23°C is 170,000-190,000 cPs.

[0033] In the present invention, the substrate can be cloth, leather, mesh, etc., without special restrictions. There is no special restriction on the cross-sectional structure of the telescopic end, which can be circular, semicircular, square, rectangular, fan-shaped, etc., or irregular in shape. In the present invention, based on the position of the suspended structure, the position of the telescopic end can be adjusted, for example, it can be parallel to the travel direction of the printing scraper, it can also be perpendicular to the travel direction of the scraper, or it can be at a certain angle to the travel direction of the scraper, such as 30°, 45°, 60°, etc.

[0034] In a preferred embodiment of the present invention, the distance between the upper end of the telescopic end and the upper surface of the wet film layer is not less than 20% of the thickness of the wet film layer. In the present invention, the upper end of the telescopic end refers to the surface of the telescopic end that is closest to the upper surface of the wet film layer. The relationship between the upper end position of the telescopic end and the distance between the upper surface of the wet film layer is controlled to avoid problems such as insufficient wet film layer, defective coating of the suspended structure, or collapse of the suspended structure before solidification due to the excessive thickness of the wet film layer in the suspended position during the retraction process of the telescopic end.

[0035] In a preferred embodiment of the present invention, the diameter of the telescopic end is 0.1-0.8 times the thickness of the wet film layer. In the present invention, if the diameter of the telescopic end is less than 0.1 times the thickness of the wet film layer, the aperture of the telescopic end used to support the wet film layer to form a hollow structure is too small, which may easily cause the wet film layer to sink, deform, and collapse due to gravity, making it difficult to maintain the formation of the suspended structure coating; if the diameter of the telescopic end is greater than 0.8 times the thickness of the wet film layer, the wet film layer above the hollow structure is too thin, which may easily cause the suspended structure coating to be defective due to the retraction of the telescopic end, and the suspended structure may also collapse before curing. For example, the diameter of the telescopic end can be any value of 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 times the thickness of the wet film layer, etc., without special restrictions.

[0036] In a preferred embodiment of the present invention, the retraction speed of the telescopic end is not less than 2m / s. In the present invention, the retraction speed of the telescopic end should not be less than 2m / s, otherwise the flow resistance and viscosity of the slurry are large, which is not conducive to the separation of the telescopic end and the wet film layer, and it is easy to carry the material, affecting the formation of the hollow structure of the wet film layer. From the actual production dimension, the retraction speed of the telescopic end is not recommended to be higher than 15m / s, and the design requirements for the telescopic component are very high. For example, the retraction speed of the telescopic end can be any value of 2m / s, 3m / s, 4m / s, 5m / s, 6m / s, 7m / s, 8m / s, 9m / s, 10m / s, 11m / s, 12m / s, 13m / s, 14m / s, 15m / s, etc., without special restrictions.

[0037] In a preferred embodiment of the present invention, the surface material of the telescopic end is selected from one of metal, inorganic non-metal, plastic, rubber and resin. In the present invention, the telescopic end can be composed of a single material or multiple materials, wherein the surface material can be selected from the above materials. For example, the surface material of the telescopic end can be one of aluminum, aluminum alloy, stainless steel, glass, polyvinyl chloride, polytetrafluoroethylene, polypropylene, polyethylene, silicone rubber / resin, etc., without special restrictions.

[0038] In a more preferred embodiment of the present invention, the surface of the telescopic end is treated with an organic group for hydrophobicity. In the present invention, the surface of the telescopic end is treated with an organic group for hydrophobicity to reduce the surface tension of the telescopic end surface, which has the following effects: (1) reducing the adhesion of the slurry to the telescopic end, (2) avoiding the entrainment of the slurry to the telescopic end when the telescopic end retracts, and having a good separation effect with the slurry, which is conducive to obtaining a high-quality suspended structure coating and can improve the durability of the telescopic end. In the present invention, when the surface material of the telescopic end is selected from metal, inorganic non-metal (such as aluminum alloy, stainless steel, glass, steel, etc.), the surface is treated with an organic group for hydrophobicity. When the surface material of the telescopic end is an organic polymer or hybrid organic polymer such as polyvinyl chloride, polytetrafluoroethylene, polypropylene, polyethylene, silicone rubber / resin, the surface may not be treated or may be treated with hydrophobicity. In addition, the surface roughness of the telescopic end surface may be no more than 20 μm, or further, no more than 10 μm, or further, no more than 5 μm, or further, no more than 3 μm.

[0039] In a more preferred embodiment of the present invention, the organic group is selected from at least one of C1-C18 hydrocarbon groups, organic silicon and organic fluorine. In the present invention, for example, a silane coupling agent, such as methyl trimethoxysilane, ethyl trimethoxysilane, n-butyl trimethoxysilane, n-octyl triethoxysilane, hexadecyl trimethoxysilane, perfluorooctyl triethoxysilane, etc., can be used to hydrophobically modify the surface of the telescopic end. This modification method is well known to those skilled in the art, such as immersing the telescopic end in a solution of the above-mentioned silane coupling agent, taking it out after the reaction for cleaning and drying, or directly spraying the solution of the silane coupling agent on the surface of the telescopic end and drying.

[0040] In a preferred embodiment of the present invention, the density of the slurry is not higher than 0.92 g / cm 3 In the present invention, by controlling the density of the slurry within a relatively small range, the anti-flow property of the slurry is improved, and the deformation caused by gravity is reduced, so as to avoid destroying the suspended structure effect of the coating.

[0041] In a preferred embodiment of the present invention, the slurry includes: 6-10wt% hollow glass microspheres, 2-4wt% thermoplastic hollow polymer microspheres and 3-5wt% polyester fibers, or a combination of two or more thereof. In the present invention, by introducing an appropriate amount of at least one of hollow glass microspheres, thermoplastic hollow polymer microspheres and polyester fibers into the slurry, on the one hand, the viscosity of the slurry can be reduced, which is beneficial for the separation of the telescopic end from the slurry when the telescopic end retracts, and on the other hand, the polyester fiber can enhance the thixotropy of the slurry and improve the three-dimensional effect, and the presence of hollow glass microspheres and thermoplastic hollow polymer microspheres can make the slurry lighter and reduce the defects of the wet film layer sinking, deforming and collapsing due to the heavy slurry. In addition, the present invention does not particularly limit other raw material components. For example, an embodiment of the present invention provides an aqueous slurry, which includes, by weight, 100%: 30-40wt% of aqueous acrylic resin, 40-50wt% of aqueous polyurethane resin, 1.5-2.0wt% of dispersant, 0.4-0.8wt% of defoaming agent, 6-10wt% of hollow glass microspheres, 2-4wt% of thermoplastic hollow polymer microspheres, 3-5wt% of polyester fibers, 0.6-2.0wt% of thickener, and 4-6wt% of cross-linking agent.

[0042] In a preferred embodiment of the present invention, the curing is selected from one of heat curing and UV light curing. In the present invention, for example, the temperature of heat curing can be 55-65°C and the time can be 24-36h; the wavelength of UV light curing can be 200-400nm and the time can be 5-60s.

[0043] Preparation example: Preparation of aqueous slurry

[0044] Preparation Example 1

[0045] A water-based slurry comprises, by weight, 34 wt% of water-based acrylic resin, 44 wt% of water-based polyurethane resin, 1.5 wt% of dispersant, 0.5 wt% of defoamer, 7 wt% of hollow glass microspheres (with a particle size of 70 μm), 3 wt% of thermoplastic hollow polymer microspheres (with a particle size of 30 μm), 4 wt% of polyester fiber (with a diameter of 100 μm), 1 wt% of thickener, and 5 wt% of cross-linking agent.

[0046] The above components were dispersed according to the proportions at a rotation speed of 800 r / min for 10 minutes to obtain an aqueous slurry.

[0047] The test results show that the viscosity of the aqueous slurry obtained in this preparation example is 181000 / 23°C, the thixotropic index is 6.7 (the ratio of the viscosity value measured at 7.5 r / min and the viscosity value measured at 75 r / min at 23°C), and the density is 0.78 g / cm 3 .

[0048] Preparation Example 2

[0049] The difference between this preparation example and preparation example 1 is that in this preparation example, hollow glass microspheres, thermoplastic hollow polymer microspheres and polyester fibers are not added, and 14 wt % of waterborne polyurethane is used to make up the difference. The other steps remain unchanged.

[0050] The test results show that the viscosity of the aqueous slurry obtained in this preparation example is 164000 / 23°C, the thixotropic index is 4.2 (the ratio of the viscosity value measured at 7.5 r / min and the viscosity value measured at 75 r / min at 23°C), and the density is 1.04 g / cm 3 .

[0051] Example 1

[0052] See also Figure 1-Figure 3 The aqueous slurry obtained in Preparation Example 1 is used to prepare a coating having a suspended structure, comprising the following steps:

[0053] S1. Place the substrate (cloth) on the printing table, so that the telescopic end (surface material is aluminum alloy) of the telescopic component extends and passes through the hollow printing position of the printing base plate in a horizontal direction perpendicular to the movement direction of the scraper;

[0054] The telescopic end is arranged in the printed base plate.

[0055] S2. After printing the slurry and obtaining a wet film layer with an average thickness of 300 μm, the telescopic end is retracted at a speed of 3 m / s to a hollow printed position away from the printing base plate, and the wet film layer is heated and cured at 60° C. for 24 hours to obtain a fabric with a suspended structure coating.

[0056] The distance between the upper end of the telescopic end and the upper surface of the wet film layer is 25% of the thickness of the wet film layer.

[0057] The diameter of the telescopic end is 0.7 times the thickness of the wet film layer.

[0058] Example 2

[0059] The difference between this embodiment and embodiment 1 is that the distance between the upper end of the telescopic end and the upper surface of the wet film layer is different, which is adjusted to 30% of the thickness of the wet film layer; the diameter of the telescopic end is different, which is adjusted to 0.5 times the thickness of the wet film layer.

[0060] Example 3

[0061] The difference between this embodiment and embodiment 1 is that the distance between the upper end of the telescopic end and the upper surface of the wet film layer is different, which is adjusted to 40% of the thickness of the wet film layer; the diameter of the telescopic end is different, which is adjusted to 0.4 times the thickness of the wet film layer.

[0062] Example 4

[0063] The difference between this embodiment and embodiment 1 is that the surface material of the telescopic end is treated with perfluorooctyl triethoxysilane for surface hydrophobicity. The other steps remain unchanged.

[0064] Example 5

[0065] The difference between this example and example 4 is that the aqueous slurry is prepared using preparation example 2 instead of preparation example 1. The remaining steps remain unchanged.

[0066] Comparative Example 1

[0067] The difference between this comparative example and Example 1 is that the distance between the upper end of the telescopic end and the upper surface of the wet film layer is different and is adjusted to 10% of the thickness of the wet film layer.

[0068] Comparative Example 2

[0069] The difference between this comparative example and Example 1 is that the diameter of the telescopic end is different and is adjusted to 0.05 times the thickness of the wet film layer.

[0070] Comparative Example 3

[0071] The difference between this comparative example and comparative example 1 is that the diameter of the telescopic end is different and is adjusted to 0.9 times the thickness of the wet film layer.

[0072] Comparative Example 4

[0073] The difference between this comparative example and Example 1 is that the retraction speed of the telescopic end is different and is adjusted to 1 m / s. The other steps remain unchanged.

[0074] Example 6

[0075] The difference between this embodiment and comparative example 4 is that the retraction speed of the telescopic end is different and is adjusted to 2 m / s. The other steps remain unchanged.

[0076] Example 7

[0077] The difference between this embodiment and comparative example 4 is that the retraction speed of the telescopic end is different and is adjusted to 10 m / s. The other steps remain unchanged.

[0078] Example 8

[0079] The difference between this embodiment and comparative example 4 is that the surface material of the telescopic end is treated with perfluorooctyl triethoxysilane for surface hydrophobicity. The other steps remain unchanged.

[0080] Example 9

[0081] The difference between this embodiment and comparative example 4 is that the surface material of the telescopic end is treated with n-butyltrimethoxysilane for surface hydrophobicity. The other steps remain unchanged.

[0082] The coatings with suspended structures prepared by the methods of Examples 1-9 and Comparative Examples 1-4 were tested, and the results are recorded in Tables 1 and 2.

[0083] Test method:

[0084] Appearance evaluation of suspended structure coating: observe whether the coating has any sinking, collapse, defects, etc.

[0085] Wet film layer adhesion percentage: measure the wet film layer area S1 adhered to the telescopic end surface after the first retraction of the telescopic end and the total surface area S2 contacting the wet film layer when the telescopic end retracts, and calculate S1 / S2×100%.

[0086] Evaluation of hanging material at the telescopic end: The hanging material on the telescopic end surface of the fabric with suspended coating was observed after 100 printings.

[0087] Table 1

[0088]

[0089]

[0090] Table 2

[0091] Example 1 Example 4 Example 7 Telescopic end hanging material evaluation No hanging material No hanging material No hanging material

[0092] As can be seen from Table 1, the methods of Examples 1-9 of the present invention can all obtain better suspended structure coatings. Even when the viscosity and thixotropy of the printing slurry used are low, the retraction speed of the telescopic end is slow, or the density is high, a better suspended structure coating can be prepared by hydrophobic treatment of the telescopic end surface. Compared with Example 1, Comparative Example 1 collapsed due to the thin wet film layer at the upper end of the telescopic end; Comparative Example 2 was too small in size for the telescopic end, so even if the thickness of the wet film layer at the upper end met the requirements, the wet film layer at the suspended position would be deformed due to insufficient support area of ​​the telescopic end; Comparative Example 3 was too thin in the upper end of the telescopic end and the size of the telescopic end was too large, so the wet film layer was more seriously damaged due to the material on the telescopic end; Comparative Example 4 was too slow in retraction speed, and material on the telescopic end appeared during the retraction of the telescopic end, which also caused defects in the hollow structure of the wet film layer.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a coating having a suspended structure, comprising the following steps: S1. Place the substrate on the printing table, so that the telescopic end of the telescopic component extends and passes through the hollow printing position of the printing base plate in the horizontal direction; The telescopic end is arranged in the printing base plate; S2, after printing the slurry and obtaining a wet film layer, retracting the telescopic end to a hollow printing position away from the printing base plate, and curing the wet film layer to obtain the coating with a suspended structure; The viscosity of the slurry at 23° C. is 170,000-190,000 cPs.

2. The method for preparing a coating having a suspended structure according to claim 1, characterized in that: The distance between the upper end of the telescopic end and the upper surface of the wet film layer is not less than 20% of the thickness of the wet film layer.

3. The method for preparing a coating having a suspended structure according to claim 1, characterized in that: The diameter of the telescopic end is 0.1-0.8 times the thickness of the wet film layer.

4. The method for preparing a coating having a suspended structure according to claim 1, characterized in that: The retraction speed of the telescopic end is not less than 2m / s.

5. The method for preparing a coating having a suspended structure according to claim 1, characterized in that: The surface material of the telescopic end is selected from one of metal, inorganic non-metal, plastic, rubber and resin.

6. The method for preparing a coating having a suspended structure according to claim 5, characterized in that: The surface of the telescopic end is treated with hydrophobicity using organic groups.

7. The method for preparing a coating having a suspended structure according to claim 6, characterized in that: The organic group is selected from at least one of a C1-C18 hydrocarbon group, an organic silicon group and an organic fluorine group.

8. The method for preparing a coating having a suspended structure according to claim 1, characterized in that: The density of the slurry is not higher than 0.92 g / cm 3 .

9. The method for preparing a coating having a suspended structure according to claim 1, characterized in that: The slurry comprises: 6-10 wt% of hollow glass microspheres, 2-4 wt% of thermoplastic hollow polymer microspheres and 3-5 wt% of polyester fibers, or a combination of two or more thereof.

10. The method for preparing a coating having a suspended structure according to claim 1, characterized in that: The curing is selected from one of heating curing and UV light irradiation curing.

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