Laser edge sealing strip and method for manufacturing same, and laser edge sealing method

Abstract

The application provides a laser sealing strip, a preparation method thereof and a laser sealing method. The laser sealing strip comprises a substrate layer, a PUR hot melt adhesive layer and a PP functional layer. The substrate layer and the PP functional layer are laminated and bonded together through the PUR hot melt adhesive layer after being respectively extruded. The laser sealing strip can effectively improve the problem that the local bonding of the plate and the laser sealing strip is not tight, thereby causing local bulging and affecting the appearance and service life of the sealing edge.

Description

Technical Field

[0001] This invention relates to the field of edge banding technology, and in particular to a laser edge banding strip and its preparation method and laser edge banding method. Background Technology

[0002] To extend the lifespan of furniture, many furniture pieces use edge banding strips to seal the edges. Currently, laser edge banding strips are widely used. These strips consist of a functional layer of a special polymer, such as polypropylene (PP resin), pre-coated on one side. A laser beam instantly activates this functional layer, causing it to melt and penetrate into the fiber structure of the furniture's cross-section, creating a mechanical riveting effect. This effectively reduces the formation of glue seams at the furniture's edges, thus improving aesthetics and lifespan. Examples include invention patent applications CN202110521211.X and CN20231097897. In the invention patent application 3.1, PP resin is used in the laser functional layer, which can achieve a good mechanical riveting effect between the furniture cross-section board and the laser edge banding strip. However, due to the anisotropy and uneven pore dispersion of the furniture cross-section board, the flow and penetration of PP resin on the furniture cross-section board is uneven during laser treatment. This can easily cause localized poor bonding between the furniture cross-section board and the laser edge banding strip, which in turn makes the furniture cross-section prone to moisture absorption, expansion and compression of the laser edge banding strip. In addition, the strong hydrophobicity of PP resin can further cause localized bulging of the furniture cross-section, affecting the aesthetics and service life of the edge banding. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a laser edge banding strip and its preparation method and laser edge banding method that can effectively improve the problem of poor local bonding between the board and the laser edge banding strip, which causes local bulging and affects the aesthetics and service life of the edge banding.

[0004] The objective of this invention is achieved through the following technical solution:

[0005] A laser-sealed edge banding strip includes a substrate layer, a PUR hot melt adhesive layer, and a PP functional layer;

[0006] The substrate layer and the PP functional layer are laminated and bonded together by the PUR hot melt adhesive layer after extrusion molding.

[0007] In one embodiment, the substrate layer comprises the following components:

[0008] ABS resin;

[0009] First antioxidant;

[0010] Calcium carbonate.

[0011] In one embodiment, a surface-printed texture layer is formed on the side of the substrate layer away from the PP functional layer.

[0012] In one embodiment, a UV protective layer is formed on the side of the surface printed texture layer away from the PP functional layer.

[0013] In one embodiment, the thickness of the substrate layer is 0.8 mm to 3.0 mm.

[0014] In one embodiment, the thickness of the PP functional layer is 0.12 mm to 0.20 mm.

[0015] In one embodiment, the thickness of the PUR hot melt adhesive layer is 0.03mm-0.08mm.

[0016] In one embodiment, the PP functional layer includes the following components:

[0017] PP resin;

[0018] Second antioxidant;

[0019] Laser treatment agent;

[0020] Laser-activated photosensitive material.

[0021] In one embodiment, the melt flow index of the PP resin is 30 g / 10 min to 100 g / 100 min.

[0022] In one embodiment, the laser processing agent is a hindered amine light stabilizer, an ultraviolet absorber, or a light shielding agent.

[0023] In one embodiment, the second antioxidant is a hindered phenolic antioxidant or a phosphite antioxidant.

[0024] In one embodiment, the laser photosensitive activator is titanium oxide and / or zinc oxide.

[0025] A method for preparing a laser edge banding strip, used to prepare the laser edge banding strip described in any of the above embodiments, the method comprising the following steps:

[0026] Obtain raw materials for the substrate layer and PP functional layer;

[0027] The substrate layer raw material and the PP functional layer raw material are respectively mixed and extruded to obtain the substrate layer and the PP functional layer independently.

[0028] The substrate layer and the PP functional layer are bonded together using PUR hot melt adhesive, so that the substrate layer and the PP functional layer are bonded together by the PUR hot melt adhesive layer, and the PUR hot melt adhesive is sandwiched between the substrate layer and the PP functional layer to form a PUR hot melt adhesive layer.

[0029] A laser edge sealing method includes the following steps:

[0030] Obtain the sheet material and the laser edge banding strip described in any of the above embodiments;

[0031] The plate is subjected to laser carbonization to form a dense carbonized layer on the cross-section of the plate.

[0032] The dense carbonized layer is roughened to form scratches that penetrate the dense carbonized layer.

[0033] The laser edge banding strip is used to perform laser edge banding on the roughened board material, so that the PP functional layer of the laser edge banding strip is positioned opposite to the dense carbonized layer, and the PP functional layer is laser-thermally fused onto the dense carbonized layer and bonded to the board material.

[0034] Compared with the prior art, the present invention has at least the following advantages:

[0035] The laser-sealed edge banding strip of this invention uses a PP functional layer as the main component for laser hot-melt bonding. Due to the good fluidity of the PP functional layer, it can penetrate well into the board material, ensuring the mechanical bonding stability between the PP functional layer and the board material. Furthermore, the substrate layer and the PP functional layer are laminated and bonded together by a PUR hot-melt adhesive layer after extrusion molding. The PUR hot-melt adhesive layer serves two purposes: firstly, it bonds the PP functional layer and the substrate layer; secondly, when the laser acts on the PP functional layer, the heat causes the PUR hot-melt adhesive layer to simultaneously... The process involves heat melting, followed by the PUR hot melt adhesive layer flowing at least partially into the interior of the board after the PP functional layer has been partially deposited. This layer then flows at least partially to the PP functional layer and comes into contact with the board, forming molecular bonds. This effectively improves the problem of poor local adhesion between the board and the laser edge banding strip. In other words, it promotes the joint bonding of the PUR hot melt adhesive layer and the PP functional layer to the cross-section of the board, effectively improving the bonding stability between the laser edge banding strip and the cross-section of the board. This also reduces local bulging of the laser edge banding strip and improves the aesthetics and service life of the edge banding on the board cross-section. Attached Figure Description

[0036] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the structure of a laser sealing strip according to an embodiment of the present invention;

[0038] Figure 2 This is a flowchart of a method for preparing a laser-sealed edge banding strip according to an embodiment of the present invention;

[0039] Figure 3 This is a flowchart of a laser edge sealing method according to an embodiment of the present invention. Detailed Implementation

[0040] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0041] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0043] This application provides a laser-sealed edge banding strip. The laser-sealed edge banding strip includes a substrate layer, a PUR hot melt adhesive layer, and a PP functional layer. The substrate layer and the PP functional layer are laminated and bonded together by the PUR hot melt adhesive layer after extrusion molding.

[0044] The aforementioned laser-sealed edge banding uses a PP functional layer as the main component for laser hot-melt bonding. Due to the good fluidity of the PP functional layer, it can penetrate well into the board, ensuring the mechanical bonding stability between the PP functional layer and the board. Furthermore, after extrusion molding, the substrate layer and the PP functional layer are laminated together by a PUR hot-melt adhesive layer. The PUR hot-melt adhesive layer serves two purposes: firstly, it bonds the PP functional layer and the substrate layer; secondly, when the laser acts on the PP functional layer, the heat causes the PUR hot-melt adhesive layer to undergo further bonding. The hot melt process, whereby the PP functional layer is at least partially cast into the interior of the board, allows the PUR hot melt adhesive layer to at least partially cast onto the PP functional layer and come into contact with the board, forming a molecular bond. This effectively improves the problem of poor local adhesion between the board and the laser edge banding strip. In other words, it promotes the joint bonding of the PUR hot melt adhesive layer and the PP functional layer to the cross-section of the board, effectively improving the bonding stability between the laser edge banding strip and the cross-section of the board, reducing local bulging of the laser edge banding strip, and improving the aesthetics and service life of the edge banding of the board cross-section.

[0045] To better understand the laser edge banding strip of this application, the following further explanation is provided:

[0046] Please refer to the following: Figure 1 One embodiment of the laser-sealed edge strip 10 includes a substrate layer 100, a PUR hot melt adhesive layer 200, and a PP functional layer 300. The substrate layer 100 and the PP functional layer 300 are laminated and bonded together by the PUR hot melt adhesive layer 200 after extrusion molding.

[0047] The aforementioned laser-sealed edge strip 10 uses the PP functional layer 300 as the main component for laser hot-melt bonding. Due to the good fluidity of the PP functional layer 300, it can penetrate well into the board, ensuring the mechanical bonding stability between the PP functional layer 300 and the board. Furthermore, the substrate layer 100 and the PP functional layer 300 are laminated and bonded together by the PUR hot-melt adhesive layer 200 after extrusion molding. The PUR hot-melt adhesive layer 200 serves two purposes: firstly, it bonds the PP functional layer 300 and the substrate layer 100; secondly, when the laser acts on the PP functional layer, the heat promotes the bonding of the PUR hot-melt adhesive layer 200. The PP functional layer 300 and the laser edge banding strip 10 are melted together. After the PP functional layer 300 is at least partially cast into the interior of the board, the PUR hot melt adhesive layer 200 is at least partially cast to the PP functional layer 300 and comes into contact with the board to form a molecular bond. This effectively improves the problem of poor local bonding between the board and the laser edge banding strip 10. In other words, it promotes the PUR hot melt adhesive layer 200 and the PP functional layer 300 to work together to bond the cross-section of the board. This effectively improves the bonding stability between the laser edge banding strip 10 and the cross-section of the board, reduces local bulging of the laser edge banding strip 10, and improves the aesthetics and service life of the edge banding of the board cross-section.

[0048] It should be noted that the PUR hot melt adhesive layer is formed at the cross-section of the board, which not only improves the bonding strength and stability between the laser edge banding strip and the board cross-section, but also reduces the moisture absorption capacity at the board cross-section due to the good water resistance of the PUR hot melt adhesive. This can effectively alleviate the problem of local bulging of the laser edge banding strip by creating areas with poor bonding strength between the laser edge banding strip and the board cross-section.

[0049] It should also be noted that the bonding strength between the PUR hot melt adhesive layer and the PP functional layer is relatively weak. However, when the laser edge banding strip is used for laser edge banding, the PUR hot melt adhesive and the PP functional layer partially undergo thermal fusion, which in turn causes the PUR hot melt adhesive to form a mechanical rivet on the PP functional layer. Therefore, the laser edge banding strip has a higher internal bonding strength after laser edge banding the cross-section of the board.

[0050] It should also be noted that mixing the PUR hot melt adhesive layer into the PP functional layer results in higher adhesion strength and stability between the PUR hot melt adhesive layer and the PP functional layer on the board surface. However, this causes localized areas of the board to come into contact with the PUR hot melt adhesive layer first, directly causing the PUR hot melt adhesive layer to bond to the cross-section of the board and seal the open pores of the cross-section. This affects the mechanical riveting effect of the PP functional layer on the board, which in turn affects the adhesion strength between the laser edge banding strip and the board surface, thus increasing the probability of laser edge banding strip peeling off. Applying the PUR hot melt adhesive layer directly to the cross-section of the board first has an even more severe impact on the adhesion strength between the laser edge banding strip and the board surface. It can be understood that the PUR hot melt adhesive layer is a moisture-curing PUR hot melt adhesive.

[0051] In one embodiment, the substrate layer comprises the following components: ABS resin; a first antioxidant; and calcium carbonate. Further, the substrate layer comprises the following components in parts by weight: 90 to 100 parts ABS resin; 0.1 to 0.3 parts first antioxidant; and 3 to 5 parts calcium carbonate, which better ensures the mechanical strength and oxidation resistance of the substrate layer. It should be noted that ABS resin is a commonly used material for the substrate layer in laser edge banding strips; therefore, this application will not elaborate further on ABS resin.

[0052] In one embodiment, the first antioxidant is a hindered phenolic antioxidant or a phosphite antioxidant. Further, the hindered phenolic antioxidant is 2,6-di-tert-butyl-4-methylphenol, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], or octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate. Further, the phosphite antioxidant is tris(2,4-di-tert-butylphenyl) phosphite or bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite.

[0053] Please refer to the following: Figure 1 In one embodiment, a surface-printed texture layer 400 is formed on the side of the substrate layer 100 away from the PP functional layer 300. Further, the thickness of the surface-printed texture layer 400 is 0.05 mm to 0.1 mm. It can be understood that the surface-printed texture layer 400 is a decorative surface layer used to carry the printed pattern, and is a relatively conventional layer structure in the laser-sealed edge strip 10. Therefore, the composition of the surface-printed texture layer 400 will not be described in detail.

[0054] Please refer to the following: Figure 1 In one embodiment, a UV protective layer 500 is formed on the side of the surface printed texture layer 400 away from the PP functional layer 300. Furthermore, the UV protective layer 500 has a more conventional layered structure in the laser sealing strip 10; therefore, the composition and other parameters of the surface printed texture layer 400 will not be described in detail.

[0055] In one embodiment, the thickness of the substrate layer is 0.8 mm to 3.0 mm, which effectively ensures mechanical strength.

[0056] In one embodiment, the thickness of the PP functional layer is 0.12mm to 0.20mm, which effectively combines with the PUR hot melt adhesive layer to achieve effective mechanical riveting of the board and allow the PUR hot melt adhesive layer to flow and contact the board, thereby ensuring improved bonding stability between the laser edge banding strip and the board's cross-section. Furthermore, if the PP functional layer is too thick, there will be excessive adhesive overflow, making it difficult for the PUR hot melt adhesive layer to contact the board's cross-section and bond. Conversely, if the PP functional layer is too thin, it will not provide sufficient mechanical riveting and will be difficult to combine with the PUR hot melt adhesive layer to form a strong bond with the board's cross-section, affecting the bonding effect. If the bonding strength of the board's cross-section is reinforced by increasing the thickness of the PUR hot melt adhesive layer, the PUR hot melt adhesive layer will quickly fuse into the PP functional layer under laser hot melting, bonding with the board's cross-section, thus affecting the full penetration of the PP functional layer into the board and consequently affecting the mechanical riveting strength between the laser edge banding strip and the board.

[0057] In one embodiment, the thickness of the PUR hot melt adhesive layer is 0.03mm-0.08mm, which effectively achieves bonding between the substrate layer and the PP functional layer, and also effectively integrates with the PP functional layer. This ensures that some of the adhesive flows to the PP functional layer and can contact and bond with the cross-section of the board, thus improving the bonding stability between the laser edge banding strip and the cross-section of the board. Furthermore, if the thickness of the PUR hot melt adhesive layer is too large, the amount of adhesive overflow will be greater, and the PUR hot melt adhesive layer will rapidly fuse to the PP functional layer under the laser hot melting action, bonding with the cross-section of the board. This will affect the full penetration of the PP functional layer into the board, thereby affecting the mechanical bonding strength between the laser edge banding strip and the board. Conversely, if the thickness of the PUR hot melt adhesive layer is too small, it will be difficult for the PUR hot melt adhesive layer to contact and bond with the cross-section of the board.

[0058] In one embodiment, the PP functional layer comprises the following components: PP resin; a second antioxidant; a laser treatment agent; and a laser-sensitive activator. Further, the PP functional layer comprises the following components in parts by weight: 40 to 60 parts PP resin; 0.05 to 0.1 parts second antioxidant; 0.8 to 2 parts laser treatment agent; and 2 to 4.8 parts laser-sensitive activator. Further, the PP functional layer also comprises the following component in parts by weight: 1.2 to 2.5 parts maleic anhydride-grafted PP resin, which better ensures rapid laser thermal fusion of the PP functional layer and better ensures the flowability and mechanical bonding strength of the PP functional layer.

[0059] In one embodiment, the melt flow index (MFR) of the PP resin is 30 g / 10 min to 100 g / 100 min. Further, the PP resin is selected from one PP resin with a melt flow index (MFR) of 30 g / 10 min to 50 g / 10 min, and also from another PP resin with a melt flow index (MFR) of 50 g / 10 min to 100 g / 10 min. Further still, the PP resin is selected from a PP resin with a melt flow index (MFR) of 60 g / 10 min to 100 g / 100 min, which better ensures the fluidity of the PP functional layer, thereby better ensuring the penetration effect of the PP functional layer into the board, and thus ensuring the mechanical riveting strength between the laser-sealed edge strip and the board.

[0060] In one embodiment, the laser processing agent is a hindered amine light stabilizer, an ultraviolet absorber, or a light shielding agent. Further, the hindered amine light stabilizer is (2,2,6,6-tetramethyl-4-hydroxypiperidine) benzoate, bis(1,2,2,6,6-pentamethyl-4-hydroxypiperidine) sebacate, or azirtri[(2,2,6,6-tetramethyl-4-hydroxypiperidine) acetic acid]. Further, the ultraviolet absorber is phenyl o-hydroxybenzoate, 2,4-dihydroxybenzophenone, or 2-(2ˊ-hydroxy-5ˊ-methylphenyl)benzotriazole. Further, the light shielding agent is carbon black, titanium dioxide, or zinc oxide.

[0061] In one embodiment, the second antioxidant is a hindered phenolic antioxidant or a phosphite antioxidant. Further, the hindered phenolic antioxidant is 2,6-di-tert-butyl-4-methylphenol, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], or octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate. Further, the phosphite antioxidant is tris(2,4-di-tert-butylphenyl) phosphite or bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite.

[0062] In one embodiment, the laser-sensitive activating material is titanium dioxide and / or zinc oxide.

[0063] This application also provides a method for preparing a laser edge-sealing strip, used to prepare the laser edge-sealing strip of any of the above embodiments. The method for preparing the laser edge-sealing strip includes the following steps: obtaining a substrate layer raw material and a PP functional layer raw material; performing a mixing and extrusion operation on the substrate layer raw material and the PP functional layer raw material respectively to independently obtain a substrate layer and a PP functional layer; using PUR hot melt adhesive to bond the substrate layer and the PP functional layer together, so that the substrate layer and the PP functional layer are bonded together by the PUR hot melt adhesive layer, and the PUR hot melt adhesive is sandwiched between the substrate layer and the PP functional layer to form a PUR hot melt adhesive layer.

[0064] The aforementioned method for preparing laser edge banding strips involves bonding the substrate layer and the PP functional layer with PUR hot melt adhesive. This creates a PUR hot melt adhesive layer sandwiched between the substrate layer and the PP functional layer. The laser edge banding strip still primarily uses the PP functional layer for laser hot melt bonding, allowing for better penetration into the board and ensuring stable mechanical bonding between the PP functional layer and the board. Furthermore, when the laser acts on the PP functional layer, the heat causes the PUR hot melt adhesive layer to melt, resulting in at least a partial flow of the PP functional layer into the board's interior. The R hot melt adhesive layer at least partially flows to the PP functional layer and comes into contact with the board to form a molecular bond. This promotes the joint bonding of the PUR hot melt adhesive layer and the PP functional layer to the cross-section of the board, effectively improving the bonding stability between the laser edge banding strip and the board cross-section and reducing local bulging of the laser edge banding strip. In addition, by performing a mixed extrusion operation on the raw materials of the substrate layer and the PP functional layer separately, that is, the substrate layer and the PP functional layer are extruded separately, the thickness uniformity of the substrate layer and the PP functional layer is well ensured, and the synergistic effect of the PP functional layer and the PUR hot melt adhesive is well ensured.

[0065] To better understand the preparation method of the laser edge banding strip of this application, the following further explanation is provided:

[0066] Please refer to the following: Figure 2 One embodiment of the laser sealing strip preparation method includes the following steps:

[0067] S100. Obtain the raw materials for the substrate layer and the PP functional layer. It is understood that the substrate layer raw materials include the following components in parts by weight: 90-100 parts ABS resin; 0.1-0.3 parts first antioxidant; 3-5 parts calcium carbonate; while the PP functional layer raw materials include the following components in parts by weight: 40-60 parts PP resin; 0.05-0.1 parts second antioxidant; 0.8-2 parts laser treatment agent; 2-4.8 parts laser photosensitizing activator.

[0068] S200: The substrate layer material and the PP functional layer material are mixed and extruded separately to obtain the substrate layer and the PP functional layer independently. It can be understood that independently mixing and extruding the substrate layer material and the PP functional layer material, i.e., extruding the substrate layer and the PP functional layer separately, ensures better uniformity of the thickness of the substrate layer and the PP functional layer, and also better ensures the synergistic effect of the PP functional layer and the PUR hot melt adhesive. However, if the substrate layer and the PP functional layer are formed by co-extrusion, it is more difficult to ensure the uniformity and controllability of the thickness of the substrate layer and the PP functional layer; furthermore, it is more difficult to achieve the formation of the PUR hot melt adhesive layer.

[0069] S300: PUR hot melt adhesive is used to bond the substrate layer and the PP functional layer together, creating a PUR hot melt adhesive layer sandwiched between them. The PUR hot melt adhesive provides bonding to the substrate layer, effectively ensuring its adhesion strength. While its adhesion to the PP functional layer is weaker, it still ensures the overall structural strength of the laser-sealed edge banding before use. The PUR hot melt adhesive layer ensures that the PP functional layer remains the primary component of the laser-sealed edge banding. The good fluidity of the PP functional layer allows it to penetrate the board effectively, ensuring stable mechanical bonding between the PP functional layer and the board. This further enhances the adhesion of the PUR hot melt adhesive layer. When the laser acts on the PP functional layer, the heat causes the PUR hot melt adhesive layer to melt as well. After at least part of the PP functional layer flows into the interior of the board, the PUR hot melt adhesive layer also flows to the PP functional layer and comes into contact with the board to form molecular bonds. This effectively improves the problem of poor local bonding between the board and the laser edge banding strip. In other words, it promotes the PUR hot melt adhesive layer and the PP functional layer to work together to bond the cross-section of the board, effectively improving the bonding stability between the laser edge banding strip and the cross-section of the board, reducing local bulging of the laser edge banding strip, and improving the aesthetics and service life of the edge banding of the board cross-section.

[0070] The aforementioned method for preparing laser edge banding strips involves bonding the substrate layer and the PP functional layer with PUR hot melt adhesive. This creates a PUR hot melt adhesive layer sandwiched between the substrate layer and the PP functional layer. The laser edge banding strip still primarily uses the PP functional layer for laser hot melt bonding, allowing for better penetration into the board and ensuring stable mechanical bonding between the PP functional layer and the board. Furthermore, when the laser acts on the PP functional layer, the heat causes the PUR hot melt adhesive layer to melt, resulting in at least a partial flow of the PP functional layer into the board's interior. The R hot melt adhesive layer at least partially flows to the PP functional layer and comes into contact with the board to form a molecular bond. This promotes the joint bonding of the PUR hot melt adhesive layer and the PP functional layer to the cross-section of the board, effectively improving the bonding stability between the laser edge banding strip and the board cross-section and reducing local bulging of the laser edge banding strip. In addition, by performing a mixed extrusion operation on the raw materials of the substrate layer and the PP functional layer separately, that is, the substrate layer and the PP functional layer are extruded separately, the thickness uniformity of the substrate layer and the PP functional layer is well ensured, and the synergistic effect of the PP functional layer and the PUR hot melt adhesive is well ensured.

[0071] In one embodiment, the substrate layer material and the PP functional layer material are mixed and extruded, including the following steps:

[0072] ABS resin, the first antioxidant, and calcium carbonate are added together into the first screw extruder and mixed and extruded to obtain the substrate layer, which effectively achieves full mixing of the components of the substrate layer and uniformity of the extrusion thickness.

[0073] PP resin, maleic anhydride-grafted PP resin, a second antioxidant, a laser treatment agent, and a laser photosensitive activator are added together into a second screw extruder and mixed and extruded to obtain a PP functional layer, which effectively achieves full mixing of the components of the PP functional layer and uniformity of the extrusion thickness.

[0074] In one embodiment, the bonding operation between the substrate layer and the PP functional layer using PUR hot melt adhesive includes the following steps:

[0075] At temperatures ranging from 35°C to 50°C, PUR hot melt adhesive is applied to the substrate layer simultaneously with the extrusion. It is understood that the substrate layer is a soft material at the time of extrusion, possessing relatively good adhesion and reactivity. Applying the PUR hot melt adhesive to the substrate layer at this temperature better ensures that the PUR hot melt adhesive and the substrate layer form molecular bonds and adhere together.

[0076] Under conditions of 35℃~50℃, the PP functional layer is bonded to the PUR hot melt adhesive at the time of extrusion. It can be understood that the PP functional layer is a soft material at the time of extrusion, possessing relatively good adhesion. This allows the PUR hot melt adhesive to be applied to the PP functional layer, better ensuring the bonding effect between the PUR hot melt adhesive and the PP functional layer.

[0077] The substrate layer and the PP functional layer are pressure-bonded under conditions of 35℃~50℃ and 0.3MPa. This means that PUR hot melt adhesive is applied to the substrate layer during extrusion, and the PP functional layer is bonded to the PUR hot melt adhesive at the same time. This can be understood as the substrate layer simultaneously serving as the receiving substrate for the PP functional layer while the PUR hot melt adhesive is being applied, and pressure is simultaneously applied to the portion of the PP functional layer in contact with the PUR hot melt adhesive for compression bonding. This further promotes the compression bonding of the PP functional layer and the substrate layer with the PUR hot melt adhesive under conditions of 35℃~50℃ and 0.3MPa, thus improving the effective adhesion of the substrate layer, the PUR hot melt adhesive layer, and the PP functional layer.

[0078] In one embodiment, the substrate layer and the PP functional layer are pressure-bonded at a temperature of 35°C to 50°C and a pressure of 0.3 MPa. Following this, the process includes a cooling and bonding step: cooling and bonding the pressure-bonded PUR hot melt adhesive, the substrate layer, and the PP functional layer together, so that the substrate layer and the PP functional layer are bonded together by the PUR hot melt adhesive layer. The PUR hot melt adhesive is sandwiched between the substrate layer and the PP functional layer to form a PUR hot melt adhesive layer, achieving the cooling and curing of the laser sealing strip. Furthermore, during the cooling and bonding and pressure bonding operations, the humidity is less than 18% RH, which better ensures the cross-linking and bonding activity of the PUR hot melt adhesive.

[0079] This application also provides a laser edge banding method. The laser edge banding method described above includes the following steps: obtaining a board material and a laser edge banding strip according to any of the above embodiments; performing a laser carbonization operation on the board material to form a dense carbonized layer on the cross-section of the board material; roughening the dense carbonized layer to form scratches penetrating the dense carbonized layer on the dense carbonized layer; and performing a laser edge banding operation on the roughened board material using the laser edge banding strip, such that the PP functional layer of the laser edge banding strip is positioned opposite to the dense carbonized layer, and the PP functional layer is laser-thermally fused onto the dense carbonized layer and bonded to the board material.

[0080] The aforementioned laser edge banding method involves laser carbonization of the board, resulting in a dense carbonized layer on the cross-section. This effectively reduces the water absorption and expansion of the board's cross-section. Combined with a roughening treatment of the dense carbonized layer, creating scratches that penetrate it, the scratches compensate for the decrease in porosity. Compared to the anisotropic penetration of raw wood, the scratches better integrate with the raw wood, forming capillary action that promotes the thermal melting penetration of the PP functional layer. This ensures the mechanical bonding strength between the PP functional layer and the board, further enhanced by the use of laser edge banding strips. Laser edge banding is performed on the roughened board material to allow the PP functional layer to be laser-melted onto the dense carbonized layer and bonded to the board. Due to the presence of the PUR hot melt adhesive layer in the laser edge banding strip, which can form molecular bonds with the dense carbonized layer, the synergistic effect of the PUR hot melt adhesive layer, PP functional layer, and dense carbonized layer effectively improves the mechanical riveting and bonding stability between the laser edge banding strip and the board material. This effectively reduces local bulging of the laser edge banding strip and improves the aesthetics and service life of the edge banding on the board material cross-section.

[0081] To better understand the laser edge banding method of this application, the following further explanation is provided:

[0082] Please refer to the following: Figure 3 One embodiment of the laser edge sealing method includes the following steps:

[0083] S010. Obtain the board material and the laser edge banding strip 10 of any of the above embodiments. It is understood that the board material is the board material with the cross-section to be edge-banded; please refer to [further details omitted]. Figure 1 The laser sealing strip 10 includes a substrate layer 100, a PUR hot melt adhesive layer 200 and a PP functional layer 300. The substrate layer 100 and the PP functional layer 300 are laminated and bonded together by the PUR hot melt adhesive layer 200 after extrusion molding.

[0084] S020. Laser carbonization is performed on the board to form a dense carbonized layer on the cross-section. This laser carbonization process is essentially a low-temperature carbonization treatment, resulting in a dense carbonized layer on the cross-section. The water absorption and expansion rate of this dense carbonized layer are significantly lower than those of raw wood, effectively reducing water absorption and expansion. This reduces areas of weaker adhesion between the laser edge banding and the board, mitigating localized bulging issues. However, the significantly reduced porosity of the carbonized layer compared to raw wood negatively impacts the penetration of the PP functional layer into the board, affecting the mechanical bonding strength. As with typical laser edge banding, controlling the carbonization at the board's cross-section is crucial.

[0085] S030. The dense carbonized layer is roughened to create scratches that penetrate the dense carbonized layer. This roughening process creates these penetrating scratches, allowing the scratches to compensate for the decrease in porosity. Compared to the anisotropic penetration of the raw wood, the scratches better integrate with the raw wood to form capillary action, promoting the thermal fusion penetration of the PP functional layer. This ensures the mechanical bonding strength between the PP functional layer and the board while further reducing the water absorption and expansion of the board's cross-section, effectively mitigating the problem of localized bulging in the laser-sealed edge banding.

[0086] S040. Laser edge sealing is performed on the roughened board material using laser edge sealing strips, so that the PP functional layer of the laser edge sealing strip is positioned opposite to the dense carbonized layer, and the PP functional layer is laser-thermally fused onto the dense carbonized layer and bonded to the board material. It is understandable that, due to the formation of a dense carbonized layer, the bonding strength between the dense carbonized layer and the PP functional layer on the side adjacent to the PP functional layer is relatively weak. Although this effectively reduces the water absorption and expansion rate at the board cross-section, thus effectively reducing local bulging of the laser edge banding, there is still a situation where the bonding strength between the PP functional layer and the dense carbonized layer is not strong enough, resulting in local bulging. However, due to the presence of the PUR hot melt adhesive layer in the laser edge banding, which can form molecular bonds with the dense carbonized layer, the synergistic effect of the PUR hot melt adhesive layer, the PP functional layer, and the dense carbonized layer effectively improves the mechanical riveting and bonding stability between the laser edge banding and the board, effectively reducing local bulging of the laser edge banding and improving the aesthetics and service life of the board cross-section edge banding.

[0087] The aforementioned laser edge banding method involves laser carbonization of the board, resulting in a dense carbonized layer on the cross-section. This effectively reduces the water absorption and expansion of the board's cross-section. Combined with a roughening treatment of the dense carbonized layer, creating scratches that penetrate it, the scratches compensate for the decrease in porosity. Compared to the anisotropic penetration of raw wood, the scratches better integrate with the raw wood, forming capillary action that promotes the thermal melting penetration of the PP functional layer. This ensures the mechanical bonding strength between the PP functional layer and the board, further enhanced by the use of laser edge banding strips. Laser edge banding is performed on the roughened board material to allow the PP functional layer to be laser-melted onto the dense carbonized layer and bonded to the board. Due to the presence of the PUR hot melt adhesive layer in the laser edge banding strip, which can form molecular bonds with the dense carbonized layer, the synergistic effect of the PUR hot melt adhesive layer, PP functional layer, and dense carbonized layer effectively improves the mechanical riveting and bonding stability between the laser edge banding strip and the board material. This effectively reduces local bulging of the laser edge banding strip and improves the aesthetics and service life of the edge banding on the board material cross-section.

[0088] In one embodiment, the moisture content of the board is 8% to 12%, which better ensures the penetration effect of the PP functional layer on the board, and thus better ensures the mechanical riveting effect between the PP functional layer and the board.

[0089] In one embodiment, the plate is subjected to laser carbonization under conditions of oxygen concentration less than 5%, ensuring the stable formation of a dense carbonized layer.

[0090] In one embodiment, the laser energy is 18 J / cm².2 ~26J / cm 2 Under these conditions, laser carbonization of the board material effectively ensures the stable formation of a dense carbonized layer.

[0091] In one embodiment, laser carbonization of the substrate is performed at a scanning speed of 22 m / min to 26 m / min, which effectively ensures the stable formation of a dense carbonized layer.

[0092] In one embodiment, the dense carbonized layer is roughened, including the following steps:

[0093] A diamond grinding wheel is used to finely polish the dense carbonized layer, achieving a thickness of 50μm to 60μm. It is understood that the formation of a micron-sized dense carbonized layer has minimal impact on the properties of the board, while effectively reducing water absorption and swelling at the board's cross-section, and ensuring effective capillary action in the wood components that will complement the board. Using a metal grinding wheel effectively achieves the formation of a 50μm to 60μm thick dense carbonized layer. Furthermore, an excessively thick dense carbonized layer makes it difficult to create nanoscale scratches, while an excessively thin layer makes it difficult to effectively reduce water absorption and swelling at the cross-section, and to ensure effective capillary action in the wood components that will complement the board.

[0094] A nanostructured abrasive wheel is used to scratch the finely polished, dense carbonized layer, creating nanoscale scratches that penetrate the layer. This nanostructured abrasive wheel effectively achieves the formation of these penetrating nanoscale scratches, ensuring that the wood components of the board can effectively form capillary action and that the PP functional layer can effectively penetrate the board.

[0095] In one embodiment, a diamond grinding wheel is used to finely polish the dense carbide layer. The specific operation is as follows: a 200-grit diamond grinding wheel is used to polish the dense carbide layer at a rotation speed of 3000 rpm to 3200 rpm and a feed rate of 5 mm / s to 5.5 mm / s. Then, an 800-grit diamond grinding wheel is used to polish the dense carbide layer at a rotation speed of 5000 rpm to 5200 rpm and a feed rate of 2 mm / s to 2.5 mm / s. Finally, a 3000-grit diamond grinding wheel is used to polish the dense carbide layer at a rotation speed of 8000 rpm to 8500 rpm and a feed rate of 0.4 mm / s to 0.5 mm / s. This effectively achieves the formation of a dense carbide layer with a thickness of 50 μm to 60 μm.

[0096] In one embodiment, a nanostructured grinding wheel is used to scratch the finely polished dense carbonized layer. The specific operation is as follows: CVD nanodiamond with a particle size of 80nm is used to grind the finely polished dense carbonized layer. The axial pressure is 0.051MPa~0.1MPa, the rotation speed is 12000rpm~15000rpm, and the feed rate is 0.2mm / s~0.5mm~s. This effectively achieves the formation of nanoscale scratches that penetrate the dense carbonized layer.

[0097] In one embodiment, under the conditions of ultrasonic vibration frequency of 20kHz to 22kHz and amplitude of 2μm to 5μm, a nanostructured grinding wheel is used to scratch the finely polished dense carbonized layer, thereby further realizing the formation of nanoscale scratches that penetrate the dense carbonized layer.

[0098] In one embodiment, a laser edge banding strip is used to perform laser edge banding on the roughened board. The operation is as follows: a laser beam is projected onto the PP functional layer so that the PP functional layer is hot-melted and simultaneously bonded to the dense carbonized layer. Both the PP functional layer and the PUR hot melt adhesive layer are bonded together with the board.

[0099] In one embodiment, under the conditions of laser power of 0.5W to 0.8W, spot diameter of 0.2mm to 0.3mm, pulse frequency of 20kHz to 50kHz, scanning speed of 22mm / s to 30mm / s, overlap rate of 30% to 45%, defocusing amount of ±0.5mm, temperature of 20℃ to 30℃, and humidity of 50% RH to 65% RH, laser edge banding strips are used to perform laser edge banding on the roughened board material, which effectively achieves stable mechanical riveting and bonding of the laser edge banding strip to the cross-section of the board material.

[0100] It is understandable that while setting a dense carbonization layer beforehand may exacerbate secondary carbonization during laser edge banding, this secondary carbonization is actually caused by excess laser energy. In practice, both primary and secondary carbonization of the board require strict control of excess laser energy. In over 90% of standardized scenarios, existing technologies can autonomously avoid carbonization through intelligent devices. For the remaining 10% of complex situations, a combination of AI algorithms and human experience can effectively avoid carbonization. Therefore, although the formation of a dense carbonization layer before laser edge banding can cause secondary carbonization and thus affect the laser edge banding effect, the existing technology and the desired effect are sufficient to effectively avoid and improve secondary carbonization. Practical operation has also verified the effective avoidance and improvement of secondary carbonization to mitigate its impact on the laser edge banding effect. Therefore, this application will not elaborate on the secondary carbonization.

[0101] In the test data, the laser heat seal prepared by the above-mentioned laser edge sealing strip preparation method using the above-mentioned group distribution ratios, when applied to the board treated by the above-mentioned laser edge sealing method, did not cause local bulging when soaked in water at a temperature of 100℃ for one week, and the peel strength after being taken out was greater than 130N.

[0102] Compared with the prior art, the present invention has at least the following advantages:

[0103] The laser-sealed edge banding strip of this invention uses a PP functional layer as the main component for laser hot-melt bonding. Due to the good fluidity of the PP functional layer, it can penetrate well into the board material, ensuring the mechanical bonding stability between the PP functional layer and the board material. Furthermore, the substrate layer and the PP functional layer are laminated and bonded together by a PUR hot-melt adhesive layer after extrusion molding. The PUR hot-melt adhesive layer serves two purposes: firstly, it bonds the PP functional layer and the substrate layer; secondly, when the laser acts on the PP functional layer, the heat causes the PUR hot-melt adhesive layer to simultaneously... The process involves heat melting, followed by the PUR hot melt adhesive layer flowing at least partially into the interior of the board after the PP functional layer has been partially deposited. This layer then flows at least partially to the PP functional layer and comes into contact with the board, forming molecular bonds. This effectively improves the problem of poor local adhesion between the board and the laser edge banding strip. In other words, it promotes the joint bonding of the PUR hot melt adhesive layer and the PP functional layer to the cross-section of the board, effectively improving the bonding stability between the laser edge banding strip and the cross-section of the board. This also reduces local bulging of the laser edge banding strip and improves the aesthetics and service life of the edge banding on the board cross-section.

[0104] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A laser edge sealing method, characterized in that, Includes the following steps: Obtain the sheet material and laser edge banding strip; The plate is subjected to laser carbonization to form a dense carbonized layer on the cross-section of the plate, which reduces the water absorption and expansion of the plate cross-section. The dense carbonized layer is roughened to form scratches that penetrate the dense carbonized layer. The scratches, combined with the log, form a capillary effect that promotes the hot melt penetration of the PP functional layer. The laser edge banding strip is used to perform laser edge banding on the roughened board material, so that the PP functional layer of the laser edge banding strip is positioned opposite to the dense carbonized layer, and the PP functional layer is laser-thermally melted onto the dense carbonized layer and bonded to the board material, and the PUR hot melt adhesive layer can be molecularly bonded to the dense carbonized layer. The laser-sealed edge banding includes a substrate layer, a PUR hot melt adhesive layer, and a PP functional layer. The substrate layer and the PP functional layer are laminated and bonded together by the PUR hot melt adhesive layer after extrusion molding.

2. The laser edge sealing method according to claim 1, characterized in that, The substrate layer comprises the following components: ABS resin; First antioxidant; Calcium carbonate.

3. The laser edge sealing method according to claim 1, characterized in that, A surface-printed texture layer is formed on the side of the substrate layer away from the PP functional layer.

4. The laser edge sealing method according to claim 3, characterized in that, A UV protective layer is formed on the side of the surface printed texture layer away from the PP functional layer.

5. The laser edge sealing method according to claim 1, characterized in that, The thickness of the substrate layer is 0.8 mm to 3.0 mm; and / or, The thickness of the PP functional layer is 0.12mm~0.20mm; and / or, The thickness of the PUR hot melt adhesive layer is 0.03mm-0.08mm.

6. The laser edge sealing method according to claim 1, characterized in that, The PP functional layer comprises the following components: PP resin; Second antioxidant; Laser treatment agent; Laser-activated photosensitive material.

7. The laser edge sealing method according to claim 6, characterized in that, The melt flow index of the PP resin is 30g / 10min to 100g / 100min.

8. The laser edge sealing method according to claim 6, characterized in that, The laser processing agent is a hindered amine light stabilizer, an ultraviolet absorber, or a light shielding agent; and / or, The second antioxidant is a hindered phenolic antioxidant or a phosphite antioxidant; and / or, the laser photosensitive activator is titanium dioxide and / or zinc oxide.

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