3D wood texture stone plastic floor and preparation method thereof

Abstract

The present application belongs to the technical field of wood floor manufacturing, and particularly relates to a 3D wood texture stone plastic floor and a preparation method thereof. The surface of the base color layer above the SPC substrate is endowed with irregularly distributed holes, so that the surface roughness of the base color layer is improved. Meanwhile, the paint of the three-dimensional wood grain layer above the base color layer penetrates from the holes and penetrates downward, so that the adhesion between the SPC substrate layer and the three-dimensional wood grain layer above it is enhanced, and the bonding is more stable. The surface roughness of the base color layer is increased by high-energy beam stimulation treatment. Meanwhile, the surface molecules of the base color layer are oxidized to generate groups with strong polarity, which improves the surface energy and makes it easy to bond with the paint of the printed three-dimensional wood grain layer, effectively improving the wettability and adhesion of the surface of the base color layer. Further, the warpage of the three-dimensional wood grain layer is effectively reduced, the decorative effect of the three-dimensional wood grain layer is improved, and the product quality of the stone plastic floor is guaranteed.

Description

Technical Field

[0001] This invention belongs to the field of wood flooring manufacturing technology, specifically relating to a stone-plastic flooring with 3D wood texture and its preparation method. Background Technology

[0002] Wood flooring mainly includes solid wood flooring, engineered wood flooring, and laminate flooring. Solid wood flooring has natural grain, giving it a natural, soft, and welcoming feel, while also being warm in winter and cool in summer, and having a pleasant tactile experience. However, the large-scale use of solid wood flooring consumes a lot of timber, resulting in high costs and potentially causing serious damage to the environment. Laminate flooring is made by cross-laminating different tree species, which to some extent overcomes the drawbacks of solid wood flooring such as expansion and contraction due to moisture. It has a low rate of expansion and contraction, good dimensional stability, and retains the natural wood grain and comfortable feel of solid wood flooring. However, laminate flooring has a complex structure and requires a high level of manufacturing expertise. Furthermore, the grain patterns of laminate flooring are not wear-resistant, are prone to fading, and are irreparable after being soaked in water, resulting in high costs. In addition, the production process of laminate flooring requires adhesives, which can easily release harmful gases such as formaldehyde, posing a potential health hazard.

[0003] Laminate flooring is made by impregnating one or more layers of special paper with thermosetting amino resin, laying it on the surface of particleboard, high-density fiberboard, or other engineered wood substrates, adding a balancing moisture-proof layer on the back, and a wear-resistant and decorative layer on the front, and then hot-pressing and molding it. Laminate flooring has excellent stain resistance, corrosion resistance, pressure resistance, wear resistance, impact resistance, and flame retardant properties. It is stable, easy to maintain, and low in cost. The surface of laminate flooring is generally decorated with printed paper, but this paper is prone to peeling off, easily damaged, and the texture is not realistic, resulting in poor simulation and decorative effects. The wear-resistant paper can easily detach from the flooring substrate during use due to foot traffic and vibration, reducing the lifespan of the wood flooring and lowering its quality and grade.

[0004] With the development of science and technology, plastics are increasingly being used in people's daily lives, and stone-plastic flooring, with PVC as its main material, is gradually gaining popularity among consumers. Stone-plastic flooring (also known as PVC sheet flooring) is a new type of floor decoration material. It uses stone powder to form a high-density, high-fiber mesh structure as a solid base layer, covered with a highly wear-resistant polymer PVC wear layer. Stone-plastic flooring boasts excellent properties such as being environmentally friendly, highly wear-resistant, waterproof and moisture-proof, fire-retardant, and recyclable.

[0005] Besides solid wood flooring with its natural grain, other types of flooring require printing patterns onto the substrate using printing processes, followed by surface treatments such as applying varnish to achieve wear resistance and scratch resistance. However, the surface decorative wood grain obtained through this method is presented as a flat pattern, lacking the visual impact of real wood grain. Furthermore, the tactile feel of this surface decorative wood grain is rough, indistinct, and appears rigid, failing to capture the texture of real wood. Therefore, when reproducing wood grain on the SPC substrate of stone-plastic flooring, in addition to reproducing its flat color and pattern, it is also necessary to reproduce a three-dimensional wood grain structure with a textured surface on the SPC substrate. This achieves a three-dimensional wood grain decorative effect that more closely resembles the feel of natural wood, resulting in SPC flooring with a 3D wood grain texture that is delicate, realistic, tactilely comfortable, and has a good three-dimensional effect. However, during the research and development of the manufacturing process for 3D wood grain SPC flooring, researchers discovered that in high- or low-temperature environments, 3D wood grain SPC flooring is prone to warping, deformation, and peeling due to thermal expansion and contraction. Meanwhile, when stone plastic flooring is exposed to environments with uneven temperature fluctuations over a long period, the moisture within the flooring will dissipate unevenly, leading to deformation. Furthermore, when installing stone plastic flooring indoors, the thickness difference between the SPC substrate layer and the 3D wood grain layer on top of the SPC substrate layer can cause the SPC substrate layer to absorb excessive moisture, resulting in tile-like warping and curling at the edges. This can even further lead to the 3D wood grain layer peeling off from the SPC substrate layer, severely impacting the lifespan and aesthetics of the 3D wood grain stone plastic flooring.

[0006] The reason lies in the fact that the 3D wood grain layer in SPC flooring has a multi-layered structure, resulting in an excessively thick paint layer applied to the SPC substrate surface to form the 3D wood grain layer. The production process involves numerous steps, and even after multiple rounds of rolling, some internal stress remains within the SPC flooring, which cannot be completely eliminated. Meanwhile, SPC flooring with a 3D wood grain texture, produced using digital printing technology, is ultra-light and ultra-thin, with a thickness of only 2-3 mm and a weight of only 2-3 kg per square meter, less than 10% of ordinary flooring materials. SPC flooring with a 3D wood grain texture also has a solid base layer composed of a high-density, high-fiber mesh structure made of stone powder, which has great hardness. However, the 3D wood grain layer above the SPC substrate layer has a different shrinkage rate than the SPC substrate layer. When the liquid paint cures to form the 3D wood grain layer, its volume shrinks. As layers of paint are applied to the SPC substrate layer, this shrinkage force increases, causing the 3D wood grain layer to wrinkle and deform more noticeably. Excessive warping leads to bulging and deformation of the 3D wood grain layer. More severe warping will reduce the adhesion between the SPC substrate and the three-dimensional wood grain layer, further leading to the peeling and detachment of the SPC substrate layer from the three-dimensional wood grain layer above it.

[0007] To address this, researchers have minimized the amount of paint applied to the SPC substrate surface. A thin paint coating can easily lead to blurred patterns, unclear wood grain, and easy wear and tear on the three-dimensional wood grain layer, resulting in a poor decorative effect. Researchers have also reduced the shrinkage rate difference between the SPC substrate and the three-dimensional wood grain layer to prevent warping and wrinkling of the three-dimensional wood grain layer. For example, patent CN101629446A provides a printed floor and its production method, which involves a first coating layer on the surface of the floor substrate, a printed pattern layer on the first coating layer, a second coating layer on the printed pattern layer, and a topcoat layer on the second coating layer. The first and second coating layers are anti-shrinkage paint layers formed by a flexible polymer composition. This addresses the problem of different shrinkage rates between the substrate and the pattern layer by adding an anti-shrinkage paint layer formed by a flexible polymer composition before printing the pattern. However, this flexible polymer composition has a certain degree of plasticity after film formation, and will undergo stretching or compression under external force, causing inaccurate ink spraying on top to form the pattern layer, further leading to significant differences in the resulting pattern.

[0008] Furthermore, researchers have attempted to directly improve the performance of SPC substrates to obtain stone-plastic flooring with not only better mechanical properties but also lower dimensional deformation rates. For example, patent CN111792876A discloses an SPC stone-plastic flooring material and the flooring thereof, which includes: 100 parts by weight of PVC resin; 220-260 parts by weight of heavy calcium carbonate; 40-80 parts by weight of nano-calcium carbonate; 2-4 parts by weight of stearic acid; 8-12 parts by weight of impact modifier; and 4-8 parts by weight of color masterbatch. The color masterbatch is composed of PVC resin, EVA wax, CI pigment yellow 139, a composite dispersant, and optional other additives; wherein the composite dispersant is selected from propylene-piperidine grafted poly-(12-hydroxystearic acid) and lauric acid diethanolamide. However, poor diffusion and miscibility of the dispersant or additives selected in the color masterbatch can easily cause the formed SPC substrate to become brittle and crack, affecting the quality of the stone-plastic flooring. Meanwhile, the masterbatch contains CI pigment yellow 139, which is prone to pigment migration, resulting in obvious color development of the prepared SPC substrate. This further leads to a large color difference when printing patterns on the SPC substrate, affecting the appearance of the stone plastic flooring.

[0009] Furthermore, researchers are continuously improving the performance of paints and coatings that cure to form a three-dimensional wood grain layer, aiming to prepare a UV-cured coating with strong adhesion, excellent wear resistance, environmental friendliness, soft gloss, and high hardness to meet diverse market demands. For example, patent CN115558401A provides a high-strength SPC floor UV-cured coating and its preparation method. This involves adding acrylic compounds, photoinitiators, and solvents to a container, mixing and stirring, adding a matting agent, and stirring again to prepare a high-strength SPC floor UV-cured coating. However, this UV-cured coating has a high viscosity, easily causing "stringing" and surface roughness during spraying. Moreover, its low solids content makes it difficult to balance hardness and elasticity, and a single spray application cannot achieve a thick film, resulting in insufficient film fullness.

[0010] Therefore, researchers hoped to find a new method to prevent the three-dimensional wood grain layer in stone-plastic flooring with 3D wood texture from warping and deforming, or even peeling off from the SPC substrate layer. This method would be efficient, easy to operate, and low in application cost. However, this problem has not yet been solved. Summary of the Invention

[0011] The present invention aims to overcome the defect in the existing technology of stone plastic flooring with 3D wood texture, in which the three-dimensional wood grain layer is prone to warping, causing the stone plastic flooring to bulge and deform. The invention provides a stone plastic flooring with 3D wood texture and its preparation method.

[0012] According to one aspect of the present invention, the applicant has discovered a method for manufacturing stone plastic flooring with a 3D wood texture by treating the surface of an SPC substrate layer.

[0013] According to the first aspect, in order to achieve the above-mentioned objective, the present invention is implemented through the following technical solution:

[0014] A method for manufacturing stone plastic flooring with 3D wood texture, comprising at least the following steps:

[0015] (S.1) The step of extruding to obtain the stone-plastic flooring substrate;

[0016] (S.2) The step of covering the surface of the stone plastic flooring substrate with a base color layer;

[0017] (S.3) The step of giving the surface of the base color layer irregularly distributed holes;

[0018] (S.4) The step of stimulating the surface of the base color layer obtained in the previous step with a high-energy beam;

[0019] (S.5) The step of applying primer to at least a portion of the surface of the base color layer obtained in the previous step, and curing the primer to obtain a primer layer;

[0020] (S.6) The step of forming, from bottom to top, a color paint layer, a pattern layer, a three-dimensional wood grain layer and a topcoat layer on at least a portion of the surface of the primer layer.

[0021] Preferably, the process of obtaining the base color layer in step (S.2) includes:

[0022] The step of covering the surface of the stone plastic flooring substrate with a base color film.

[0023] Preferably, the base color layer includes at least one or a combination of polyvinyl chloride resin, colorant, plasticizer, heat stabilizer, and lubricant.

[0024] Preferably, the base color layer is white and has a thickness of 0.05 to 0.15 mm.

[0025] Preferably, the process of giving the surface of the base color layer irregularly distributed holes in step (S.3) includes the step of making the surface of the base color layer contact the abrasive and thus be polished.

[0026] Preferably, the surface roughness Ra value of the base color layer after contact with the abrasive is 0.3 to 1.6 μm.

[0027] Preferably, the abrasive is any one of a belt sander, a belt grinder, or a belt polisher.

[0028] Preferably, the abrasive tool includes one or more combinations of abrasive belts, sandpaper, and gauze.

[0029] Preferably, the process of stimulating the surface of the base color layer with a high-energy beam in step (S.4) includes:

[0030] The step of subjecting the surface of the base color layer to high-frequency, high-voltage corona discharge.

[0031] Preferably, the current of the high-frequency high-voltage corona discharge is 4 to 8 A.

[0032] Preferably, the surface tension of the base color layer after being stimulated by a high-energy beam is 36-40 mN / m.

[0033] Preferably, the surface of the base color layer is subjected to a high-frequency high-voltage corona discharge rate of 15–30 m / min.

[0034] Preferably, the distance between the surface of the base color layer and the discharge electrode to which high-frequency high-voltage electricity is applied is 2 to 5 cm.

[0035] Preferably, the primer in step (S.5) includes at least a photocrosslinking resin and a photoinitiator.

[0036] Preferably, the photocrosslinking resin includes any one or more combinations of unsaturated polyester, epoxy resin, acrylic resin, acrylic-modified polyurethane resin, acrylic-modified silicone resin, acrylic-modified epoxy resin, waterborne epoxy acrylate, waterborne polyurethane acrylate, and waterborne polyester acrylic.

[0037] Preferably, the photoinitiator includes any one of free radical polymerization initiators, cationic polymerization initiators, energy transfer initiators, and ionic reaction initiators.

[0038] Preferably, the amount of primer applied to the surface of the base coat in step (S.5) is 10-15 g / m². 2 .

[0039] Preferably, the paint layer in step (S.6) is white, and the amount of paint used in the paint layer is 15-25 g / m³. 2 .

[0040] Preferably, the process of forming the patterned layer in step (S.6) includes:

[0041] The step of coating at least a portion of the surface of the paint layer with ink to form a wood grain pattern and then curing it to obtain the pattern layer.

[0042] Preferably, the amount of ink used in the pattern layer in step (S.6) is 6-10 g / m². 2 .

[0043] Preferably, the process of forming the three-dimensional wood grain layer in step (S.6) includes:

[0044] The step of covering at least a portion of the surface of the pattern layer with a three-dimensional wood grain layer having a three-dimensional structure.

[0045] Preferably, the process of forming the topcoat layer in step (S.6) includes:

[0046] The step of coating at least a portion of the surface of the three-dimensional wood grain layer with a topcoat and curing it to obtain the topcoat layer.

[0047] Preferably, the amount of topcoat used in step (S.6) is 10-15 g / m². 2 .

[0048] According to another aspect of the invention, the applicant has discovered a stone-plastic floor with a 3D wood texture.

[0049] According to the second aspect, in order to achieve the above-mentioned objective, the present invention is implemented through the following technical solution:

[0050] A stone-plastic floor with a 3D wood texture prepared by the method described above.

[0051] Therefore, the present invention has the following beneficial effects:

[0052] During the research and development of the production process for 3D wood-textured SPC flooring, after repeated experiments, the applicant discovered that, compared to SPC substrates, the three-dimensional wood grain layer in 3D wood-textured SPC flooring is extremely prone to edge warping and protrusion deformation. This is because the three-dimensional wood grain layer in 3D wood-textured SPC flooring has a multi-layered structure, resulting in an excessively thick paint layer on the SPC substrate surface used to form the three-dimensional wood grain layer. Furthermore, due to the numerous production processes, even after multiple rounds of rolling, certain internal stresses remain within the SPC flooring and cannot be completely eliminated. Meanwhile, SPC flooring with 3D wood grain texture, produced using digital printing technology, is ultra-light and ultra-thin, with a thickness of only 2-3 mm and a weight of only 2-3 kg per square meter, less than 10% of ordinary flooring materials. SPC flooring with 3D wood grain texture also features a solid SPC base layer with a high-density, high-fiber mesh structure composed of stone powder, resulting in high hardness. The shrinkage rate differs between the three-dimensional wood grain layer above the SPC substrate layer and the SPC substrate layer. When liquid paint cures to form a three-dimensional wood grain layer, its volume shrinks. As layers of paint are applied to the SPC substrate layer, this shrinkage force increases and accumulates, gradually reaching a maximum. Wrinkling and bulging deformation of the three-dimensional wood grain layer become increasingly apparent. Once this maximum shrinkage force exceeds the adhesive force between the SPC substrate and the three-dimensional wood grain layer, relative slippage occurs between them, reducing adhesion and ultimately causing the SPC substrate layer to peel off from the three-dimensional wood grain layer above it. This is consistent with the more pronounced peeling of the SPC substrate layer from the three-dimensional wood grain layer at warped areas. Further investigation by the applicant revealed a noticeable oily exudate on the surface of the white PVC film covering the SPC substrate at the peeling areas. The continuous accumulation of these precipitated oily substances reduces the surface adhesion of the white PVC film, further decreasing the bonding force between the SPC substrate and the 3D wood grain layer. This makes it easy for color overlap and inaccurate patterns to occur when printing the 3D wood grain layer directly on the SPC substrate, further affecting the simulation effect of the stone plastic floor with 3D wood texture and resulting in poor decorative effect.

[0053] The applicant's inventive discovery, through simply adding a surface treatment step to the base color layer above the SPC substrate, increases the surface roughness of the base color layer, significantly enhancing its surface energy. This strengthens the adhesion between the SPC substrate layer and the 3D wood grain layer above it, resulting in more stable bonding and superior peel resistance. Simultaneously, it effectively improves the wettability of the base color layer surface, making it easier to bond with the paint of the printed 3D wood grain layer and reducing the warping of the 3D wood grain layer. This further enhances the decorative effect of the 3D wood grain layer and improves the product quality of SPC flooring with 3D wood texture. Detailed Implementation

[0054] The present invention will be further described below with reference to specific embodiments. Those skilled in the art will be able to implement the present invention based on these descriptions. Furthermore, the embodiments of the present invention described below are generally only some, not all, of the embodiments of the present invention. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0055] According to one aspect of the present invention, the applicant has discovered a method for manufacturing stone plastic flooring with a 3D wood texture by treating the surface of an SPC substrate layer.

[0056] According to the first aspect, in order to achieve the above-mentioned objective, the present invention is implemented through the following technical solution:

[0057] A method for manufacturing stone plastic flooring with 3D wood texture, comprising at least the following steps:

[0058] (S.1) The step of extruding to obtain the stone-plastic flooring substrate;

[0059] (S.2) The step of covering the surface of the stone plastic flooring substrate with a base color layer;

[0060] (S.3) The step of giving the surface of the base color layer irregularly distributed holes;

[0061] (S.4) The step of stimulating the surface of the base color layer obtained in the previous step with a high-energy beam;

[0062] (S.5) The step of applying primer to at least a portion of the surface of the base color layer obtained in the previous step, and curing the primer to obtain a primer layer;

[0063] (S.6) The step of forming, from bottom to top, a color paint layer, a pattern layer, a three-dimensional wood grain layer and a topcoat layer on at least a portion of the surface of the primer layer.

[0064] During the research and development of the production process for 3D wood-textured SPC flooring, after repeated experiments, the applicant discovered that, compared to SPC substrates, the three-dimensional wood grain layer in 3D wood-textured SPC flooring is extremely prone to edge warping and protrusion deformation. This is because the three-dimensional wood grain layer in 3D wood-textured SPC flooring has a multi-layered structure, resulting in an excessively thick paint layer on the SPC substrate surface used to form the three-dimensional wood grain layer. Furthermore, due to the numerous production processes, even after multiple rounds of rolling, certain internal stresses remain within the SPC flooring and cannot be completely eliminated. Meanwhile, SPC flooring with 3D wood grain texture, produced using digital printing technology, is ultra-light and ultra-thin, with a thickness of only 2-3 mm and a weight of only 2-3 kg per square meter, less than 10% of ordinary flooring materials. SPC flooring with 3D wood grain texture also features a solid SPC base layer with a high-density, high-fiber mesh structure composed of stone powder, resulting in high hardness. The shrinkage rate differs between the three-dimensional wood grain layer above the SPC substrate layer and the SPC substrate layer. When liquid paint cures to form a three-dimensional wood grain layer, its volume shrinks. As layers of paint are applied to the SPC substrate layer, this shrinkage force increases and accumulates upwards, reaching a maximum at the very top of the three-dimensional wood grain layer. Wrinkling and bulging deformation of the three-dimensional wood grain layer become increasingly pronounced. Once this maximum shrinkage force exceeds the adhesive force between the SPC substrate and the three-dimensional wood grain layer, relative slippage occurs between them, reducing the adhesion and ultimately causing the SPC substrate layer to peel off from the three-dimensional wood grain layer above it. This is consistent with the more pronounced peeling of the SPC substrate layer from the three-dimensional wood grain layer above it at warped areas. Further investigation by the applicant revealed a noticeable oily exudate on the surface of the white PVC film covering the SPC substrate at the peeling areas.

[0065] Research revealed that flooring manufacturers typically cover the SPC substrate's original color by pasting or coating a base color film onto the substrate. Over time, small-molecule processing aids, plasticizers, lubricants, and other substances in the base color film migrate to the surface, forming a noticeable oily substance. This accumulated oily substance on the base color surface makes it easy for color overlap and inaccurate patterns to occur when printing a 3D wood grain layer directly onto the substrate, further affecting the simulation effect of the 3D wood texture in the SPC flooring and resulting in a poor decorative effect.

[0066] Therefore, the applicant innovatively treats the surface of the base color layer above the SPC substrate to remove the oily substances that precipitate on the surface of the base color layer, effectively preventing the continuous accumulation of oily substances and avoiding color overlap and inaccurate patterns when printing the three-dimensional wood grain layer directly on the substrate. Furthermore, by giving the surface of the base color layer above the SPC substrate irregularly distributed pores, the surface roughness of the base color layer is improved. Simultaneously, this facilitates the paint of the three-dimensional wood grain layer above the base color layer to enter and penetrate downwards through the pores, enhancing the adhesion between the SPC substrate layer and the three-dimensional wood grain layer above it, resulting in more stable bonding and effectively improving the deformation resistance of the 3D wood grain stone plastic flooring, preventing warping and wrinkling. In addition, the multiple irregularly distributed pores on the surface of the base color layer contribute to its high compressive strength, lightweight, non-absorbent, non-breathable, wear-resistant, and non-degradable properties, which can improve the thermal insulation performance of the 3D wood grain stone plastic flooring. It can also act as a wave absorber, achieving sound reduction and noise reduction, thus enhancing the practicality of the 3D wood-textured stone plastic flooring.

[0067] In addition, the applicant further induces the chemical bonds of the base color layer molecules to break and degrade by subjecting the surface to high-energy beam stimulation treatment, thereby increasing its surface roughness. During the high-energy beam stimulation treatment, a large amount of strong oxidants such as ozone are also generated, causing the surface molecules of the base color layer to oxidize and produce highly polar groups such as carbonyl groups and peroxides, forming a polar surface layer. This increases its surface energy, making it easier for the paint on the printed 3D wood grain layer to adhere. Simultaneously, it removes oil, moisture, and dirt from the surface of the base color layer. Using high-energy beams to erode the surface of the base color layer significantly improves its wettability and adhesion. This further effectively reduces the warpage rate of the 3D wood grain layer, improves its decorative effect, and ensures the product quality of the 3D wood grain stone plastic flooring.

[0068] A primer is applied to at least a portion of the surface of the base color layer after the above treatment, and then the primer is cured to form a primer layer. From bottom to top, a color paint, an ink layer to form a color pattern layer, a paint layer to form a three-dimensional wood grain layer, and a topcoat to protect the three-dimensional wood grain layer and provide other functional properties (such as antibacterial, antistatic, and wear-resistant properties) are sequentially applied to at least a portion of the surface of the primer layer, thereby forming a color paint layer, a pattern layer, a three-dimensional wood grain layer, and a topcoat layer.

[0069] In a preferred embodiment of the present invention, the process of obtaining the base color layer in step (S.2) includes:

[0070] The step of covering the surface of the stone plastic flooring substrate with a base color film.

[0071] In a preferred embodiment of the present invention, the stone-plastic flooring substrate (i.e., SPC substrate) and the base color film (i.e., PVC film) can be laminated together online. The raw materials constituting the SPC substrate and their additives are added to the main extruder, where they are melted and extruded into the main runner of the die, then extruded from the die to form the SPC substrate layer. The PVC film constituting the base color layer is then unwound and online rolled together with the obtained SPC substrate layer to obtain an SPC substrate layer with a surface covered by the PVC film.

[0072] In another preferred embodiment of the present invention, the SPC substrate and the base color film (i.e., PVC film) can also be co-extruded together. The raw materials constituting the SPC substrate and their additives are added to the main extruder, where they are melted and extruded into the main runner of the die, then extruded from the die to form the SPC substrate layer. The PVC raw materials constituting the PVC film and their additives are added to the auxiliary extruder, where they are melted and extruded into the auxiliary runner of the die, then diffused in the co-extrusion casting space of the die to coat the SPC substrate layer. After heat exchange through the cooling runner plate in the die, the layer solidifies and is shaped, finally extruded from the die to obtain an SPC substrate layer with a PVC film covering its surface.

[0073] In another preferred embodiment of the invention, the SPC substrate is obtained by extrusion molding. After the SPC substrate is extruded, its surface is coated with one or more layers of white paint, thereby forming a base color layer on the surface of the SPC substrate.

[0074] Covering the SPC substrate with one or more layers of PVC film or white paint masks the underlying color of the SPC substrate, effectively preventing color overlap, inaccurate color development, and significant color differences during subsequent color pattern printing. The SPC substrate and PVC film are bonded together online, effectively shortening the process, simplifying the workflow, improving controllability, and increasing production efficiency. In contrast, the surface of PVC film bonded to the SPC substrate through co-extrusion is very smooth, resulting in poor printing quality and even ghosting. Furthermore, applying white paint to the SPC substrate has a strong, persistent odor that can be harmful to health. It is also expensive and prone to problems such as sagging, yellowing, localized wrinkling, and cracking on the SPC substrate surface. Additionally, the evaporation of moisture and solvents in the white paint can expose the underlying substrate color, further leading to unstable colors and significant color differences in subsequent printing processes. Moreover, the long drying time and large space required for white paint reduce the manufacturing efficiency of SPC flooring.

[0075] In a preferred embodiment of the present invention, the base color layer comprises at least one or more combinations of polyvinyl chloride resin, colorant, plasticizer, heat stabilizer, and lubricant.

[0076] The main component of the base color layer (i.e., the base color film) is polyvinyl chloride resin (PVC). Due to its low coefficient of linear expansion, PVC possesses excellent fire resistance and flame retardancy. Simultaneously, PVC exhibits stable chemical properties, outstanding resistance to organic solvents, and excellent corrosion resistance. Suitable colorants can be added to the base color film according to the final color requirements of the SPC flooring product, thereby achieving masking of the SPC substrate's own color. This further prevents color overlap, inaccurate color development, and significant color differences in the printed patterns on the SPC flooring. Because the viscous flow temperature and degradation temperature of the base color film are close, it is highly susceptible to various forms of degradation during processing, leading to a loss of performance. Therefore, heat stabilizers and lubricants need to be added to the base color film formulation to improve its thermal stability. This also reduces the friction between PVC molecular chains in the base color film, preventing PVC from adhering to equipment after melting and facilitating demolding during extrusion molding. Adding plasticizers to the base color film formulation softens the PVC, effectively reducing the processing temperature of the base color film. PVC plasticizers are often small-molecule phthalate esters. In the PVC system, plasticizers do not participate in the polymerization of the PVC molecular chain, but rather bind to the PVC molecular chain through hydrogen bonds or van der Waals forces. Therefore, they often volatilize, migrate, or leach out during use. The migration of plasticizers can easily cause the base film to harden, become brittle, and even break. Plasticizers precipitated from the surface of the base film can also cause environmental pollution.

[0077] In another preferred embodiment of the present invention, the base color layer may further include one or more of the following: light stabilizer, antioxidant, impact modifier, filler, processing aid, antistatic agent, flame retardant, and bioinhibitor.

[0078] Light stabilizers prevent UV degradation of PVC in the base film. Antioxidants prevent oxygen from degrading PVC. Impact modifiers improve the toughness of PVC. Fillers reduce production costs. Processing aids improve processing performance and thermoforming properties. Antistatic agents reduce static electricity buildup on the base film surface, eliminating potential static hazards. Flame retardants improve the flame retardant properties of the base film. Bioinhibitors inhibit bacteria and mold growth, preventing microbial degradation of the base film and enhancing its antibacterial properties.

[0079] In a preferred embodiment of the present invention, the base color layer is white and has a thickness of 0.05 to 0.15 mm.

[0080] In a preferred embodiment of the present invention, the softening temperature of the base color layer is 70-85°C.

[0081] When the surface temperature of the base color layer is between 70 and 85°C, the base color layer begins to soften and become viscous. Because the PVC in the base color layer has poor thermal stability, continued heating to above 120°C for an extended period will cause it to decompose, slowly releasing hydrogen chloride gas, which will cause the base color layer to change color.

[0082] In a preferred embodiment of the present invention, the process of giving the surface of the base color layer irregularly distributed holes in step (S.3) includes:

[0083] The process involves bringing the surface of the base coat into contact with the abrasive and then polishing it.

[0084] The surface of the base color layer is sanded and polished using flexible abrasives and fine abrasive particles or other polishing media, removing oily substances, bubbles, wood burrs, dust particles, etc. Simultaneously, sanding creates irregularly distributed pores on the base color layer surface, increasing its roughness and further enhancing adhesion. Furthermore, this sanding facilitates the entry and penetration of paint or coatings used to form the three-dimensional wood grain layer above the base color layer, promoting stronger adhesion and more stable bonding between the base color layer and the SPC substrate layer, as well as the three-dimensional wood grain layer above it. This further effectively enhances the deformation resistance of the SPC flooring with 3D wood grain, preventing warping and wrinkling. Additionally, the above design effectively reduces the surface saturation of the base color layer, lowering its gloss. This increases diffuse reflection and reduces specular reflection, resulting in a matte finish on the surface of the 3D wood grain SPC flooring.

[0085] In a further preferred embodiment of the invention, the process of giving the base color layer surface irregularly distributed holes in step (S.3) includes: bringing the base color layer surface into contact with an abrasive tool for sanding. The sanding method includes hand sanding and / or machine sanding. Machine sanding is faster, allows for large-area sanding, helps improve production efficiency, and produces a more uniform sanding finish.

[0086] In a further preferred embodiment of the present invention, the process of giving the surface of the base color layer irregularly distributed holes in step (S.3) includes the step of bringing the surface of the base color layer into contact with an abrasive tool for polishing. The polishing method includes one or more combinations of dry polishing, wet polishing, oil polishing, wax polishing, polishing paste polishing, electrolytic polishing, ultrasonic polishing, magnetic abrasive polishing, and fluid polishing.

[0087] In a further preferred embodiment of the invention, the process of giving the base coat surface irregularly distributed holes in step (S.3) includes: bringing the base coat surface into contact with an abrasive tool for polishing. The dry polishing includes one or more combinations of coarse polishing, flat polishing, and fine polishing. Coarse polishing can remove oily substances, air bubbles, wood burrs, dust particles, etc., from the base coat surface. Flat polishing often uses sandpaper or abrasive cloth wrapped with small wood blocks or hard rubber to level the surface, making the base coat surface smoother. Fine polishing requires a higher degree of abrasive particle coarseness, often using finer abrasive particles, which helps increase the smoothness of the base coat surface and results in better polishing.

[0088] In a further preferred embodiment of the present invention, the process of giving the base coat surface irregularly distributed holes in step (S.3) includes: bringing the base coat surface into contact with the abrasive tool for sanding. The sanding direction is along the wood grain. Avoid horizontal or irregular sanding that would leave messy sanding marks on the base coat surface. When using different types of abrasive, the sanding direction should be changed by 30° to 45° from the previous sanding direction to avoid carrying coarse abrasive particles into the next finer sanding operation. During sanding, care should be taken to sand lightly to avoid damaging, collapsing, or deforming the lines, edges, and other protruding parts of the base coat surface, affecting the smoothness and aesthetics of its lines and edges.

[0089] In a preferred embodiment of the present invention, the surface roughness Ra value of the base color layer after contact with the abrasive is 0.3 to 1.6 μm.

[0090] In a preferred embodiment of the present invention, the abrasive is any one of a belt sander, a belt grinder, or a belt polisher.

[0091] In a preferred embodiment of the present invention, the abrasive tool includes one or more combinations of abrasive belts, abrasive paper, and gauze.

[0092] In a further preferred embodiment of the present invention, the abrasive tool includes an abrasive belt with a mesh size of 120 to 320. When the mesh size of the abrasive belt is higher than 320 and the surface roughness Ra value of the base color layer after contact with the abrasive tool is lower than 0.3 μm, the finer the abrasive particles, the smoother and flatter the surface of the base color layer after being sanded by the abrasive belt, which easily leads to a decrease in the adhesion of the base color layer surface. When the mesh size of the abrasive belt is lower than 120 and the surface roughness Ra value of the base color layer after contact with the abrasive tool is higher than 1.6 μm, the abrasive particles are too coarse, and the surface of the base color layer after being sanded by the abrasive belt is too rough. The effective contact area between the base color layer and the SPC substrate layer and the three-dimensional wood grain layer is too small, the pressure is too high, resulting in excessive frictional resistance, excessive wear, and poor wear resistance. In addition, the excessively rough surface of the base color layer after being sanded by the abrasive belt results in a large number of pits. During subsequent printing, more primer needs to be applied to the surface of the base color layer to fill the pits to prevent affecting the clarity of the pattern.

[0093] In a preferred embodiment of the present invention, the process of subjecting the surface of the base color layer to high-energy beam stimulation in step (S.4) includes:

[0094] The step of subjecting the surface of the base color layer to high-frequency, high-voltage corona discharge.

[0095] The main component of the base color film is PVC, a non-polar polymer with low surface tension. Most known paints and adhesives used to form three-dimensional wood grain layers are difficult to adhere firmly to the surface of the base color film. By subjecting the base color layer surface to corona discharge, the chemical bonds of the PVC molecules are broken and degraded, increasing its surface roughness. During the corona discharge process, a large amount of ozone is also generated. Ozone is a strong oxidant that oxidizes PVC molecules, producing highly polar groups such as carbonyl and peroxide groups, thereby increasing its surface energy. This results in higher adhesion of the base color layer, greater affinity with paints or coatings, and easier bonding with the paint used to print the three-dimensional wood grain layer. Simultaneously, it removes oil, moisture, and dirt from the surface of the base color layer, contributing to improved visual effects. Furthermore, high frequency and high voltage (high-frequency AC voltage up to 5000–15000 V / m) are used... 2 Corona discharge is applied to the surface of the treated base layer to generate low-temperature plasma, causing a free radical reaction on the surface of the base layer and cross-linking of the polymer. This increases its wettability to polar solvents, making it easier for paints and other substances to penetrate. This further effectively reduces the warpage rate of the 3D wood grain layer, improves its decorative effect, and ensures the product quality of the 3D wood grain stone-plastic flooring.

[0096] In a preferred embodiment of the present invention, the current of the high-frequency high-voltage corona discharge is 4 to 8 A.

[0097] In a preferred embodiment of the present invention, the surface tension of the base color layer surface after being stimulated by a high-energy beam is 36-40 mN / m.

[0098] When the surface tension of the base coat layer after high-energy beam stimulation is below 36 mN / m and the current of the high-frequency high-voltage corona discharge is below 4 A, the wettability of the base coat layer surface does not improve significantly and its viscosity is very poor, making it difficult to coat the surface with paint for printing the three-dimensional wood grain layer, and the three-dimensional wood grain layer is difficult to display. When the surface tension of the base coat layer after high-energy beam stimulation is above 40 mN / m and the current of the high-frequency high-voltage corona discharge is above 8 A, film adhesion easily occurs on the surface of the base coat layer, and the paint sticks back. More seriously, corona breakdown can occur, creating micropores and damaging the sealing and barrier properties of the base coat layer.

[0099] In a preferred embodiment of the present invention, the surface of the base color layer is subjected to a high-frequency high-voltage corona discharge rate of 15 to 30 m / min.

[0100] The high-frequency, high-voltage corona discharge rate on the surface of the base color layer must be consistent with the transmission speed of the SPC substrate on the production line. This ensures stable output power during corona treatment and further guarantees stable output voltage, resulting in better corona treatment performance.

[0101] In a preferred embodiment of the present invention, the distance between the surface of the base color layer and the discharge electrode to which high-frequency high-voltage electricity is applied is 2 to 5 cm.

[0102] When the distance between the base layer surface and the discharge electrode applying high-frequency high-voltage electricity is less than 2cm, the energy released by the discharge electrode is very likely to cause corona breakdown, damaging the sealing and barrier performance of the base layer. When the distance between the base layer surface and the discharge electrode applying high-frequency high-voltage electricity is greater than 5cm, the energy released by the discharge electrode is dispersed into a larger space, the corona treatment intensity decreases, and the treatment effect deteriorates.

[0103] In another preferred embodiment of the present invention, the process of subjecting the surface of the base color layer to high-energy beam stimulation in step (S.4) includes:

[0104] The step of exciting the surface of the base color layer with a laser beam.

[0105] By using a laser beam to treat the surface of the base color layer, most of the laser light is absorbed by the surface of the base color layer, while a small portion is reflected away. This alters the composition and microstructure of the base color layer surface, thereby increasing its roughness.

[0106] In a preferred embodiment of the present invention, the primer in step (S.5) includes at least a photocrosslinking resin and a photoinitiator.

[0107] In a preferred embodiment of the present invention, the photocrosslinking resin includes any one or more combinations of unsaturated polyester, epoxy resin, acrylic resin, acrylic-modified polyurethane resin, acrylic-modified silicone resin, acrylic-modified epoxy resin, waterborne epoxy acrylate, waterborne polyurethane acrylate, and waterborne polyester acrylic.

[0108] In a preferred embodiment of the present invention, the photoinitiator includes any one of free radical polymerization initiators, cationic polymerization initiators, energy transfer initiators, and ionic reactive initiators.

[0109] In a preferred embodiment of the present invention, the amount of primer applied to the surface of the base coat in step (S.5) is 10-15 g / m². 2 .

[0110] In a preferred embodiment of the present invention, the paint layer in step (S.6) is white, and the amount of paint used in the paint layer is 15-25 g / m³. 2 .

[0111] In a preferred embodiment of the present invention, the process of forming the patterned layer in step (S.6) includes:

[0112] The step of coating at least a portion of the surface of the paint layer with ink to form a wood grain pattern and then curing it to obtain the pattern layer.

[0113] In a preferred embodiment of the present invention, the amount of ink used in the pattern layer in step (S.6) is 6-10 g / m². 2 .

[0114] In a preferred embodiment of the present invention, the process of forming a three-dimensional wood grain layer in step (S.6) includes the step of covering at least a portion of the surface of the pattern layer with a three-dimensional wood grain layer having a three-dimensional structure.

[0115] In a preferred embodiment of the present invention, the process of forming the topcoat layer in step (S.6) includes:

[0116] The step of coating at least a portion of the surface of the three-dimensional wood grain layer with a topcoat and curing it to obtain the topcoat layer.

[0117] In a preferred embodiment of the present invention, the amount of topcoat used in step (S.6) is 10-15 g / m². 2 .

[0118] According to another aspect of the invention, the applicant has discovered a stone-plastic floor with a 3D wood texture.

[0119] According to the second aspect, in order to achieve the above-mentioned objective, the present invention is implemented through the following technical solution:

[0120] A stone-plastic floor with a 3D wood texture prepared by the method described above.

[0121] Example 1

[0122] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture, including the following steps:

[0123] (S.1) The raw materials and additives constituting the SPC substrate are added to the main extruder, the raw materials and additives constituting the substrate are melted by the main extruder and extruded into the main channel of the die, and then extruded from the die to form an SPC substrate layer.

[0124] (S.2) A PVC white film with a thickness of 0.07 mm (softening temperature of 80°C) constituting the base color layer is unwound and rolled together online with the SPC substrate layer obtained in step (S.1) to obtain an SPC substrate layer with the surface covered by the PVC white film; (S.3) The surface of the PVC white film is sanded using a belt sander (240 mesh) so that the surface roughness Ra value of the sanded PVC white film is 0.6 μm;

[0125] (S.4) A high-frequency high-voltage electric current of 6A and 30m / min is applied to the surface of the PVC white film after sanding in step (S.3) using a corona treatment machine to perform corona discharge, so that the surface tension of the PVC white film after corona treatment is 38mN / m.

[0126] (S.5) Apply a primer to the surface of the corona-treated PVC white film obtained in step (S.4), using 12 g / m² of primer. 2 Then, the primer is irradiated with 160w / cm ultraviolet light generated by a medium-pressure Hg lamp to cure the primer and obtain the primer layer.

[0127] (S.6) The surface of the primer layer obtained in step (S.5) is coated from bottom to top with color paint, ink to form the pattern layer, paint or coating to form the three-dimensional wood grain layer, and topcoat to protect the three-dimensional wood grain layer. Then, it is irradiated with 160w / cm ultraviolet light generated by a medium-pressure Hg lamp, thereby sequentially forming the color paint layer, pattern layer, three-dimensional wood grain layer, and topcoat layer. The amount of color paint used is 17g / m². 2 The amount of ink used to form the pattern layer is 7g / m². 2 The amount of paint used to form the three-dimensional wood grain layer is 205g / m². 2 The amount of topcoat used is 12g / m².2 .

[0128] This embodiment also provides a stone-plastic floor with a 3D wood texture prepared by the method described above.

[0129] Example 2

[0130] The difference between this embodiment and Embodiment 1 is that:

[0131] This embodiment provides a method for manufacturing stone-plastic flooring with a 3D wood texture. In step (S.3), the abrasive belt is 120 mesh, resulting in a surface roughness Ra value of 1.6 μm for the sanded PVC white film. Everything else is the same as in Example 1.

[0132] Example 3

[0133] The difference between this embodiment and Embodiment 1 is that:

[0134] This embodiment provides a method for manufacturing stone-plastic flooring with a 3D wood texture. In step (S.3), the abrasive belt is 180 mesh, resulting in a surface roughness Ra value of 0.8 μm for the sanded PVC white film. Everything else is the same as in Example 1.

[0135] Example 4

[0136] The difference between this embodiment and Embodiment 1 is that:

[0137] This embodiment provides a method for manufacturing stone-plastic flooring with a 3D wood texture. In step (S.3), the abrasive belt is 320 mesh, resulting in a surface roughness Ra value of 0.3 μm for the sanded PVC white film. Everything else is the same as in Example 1.

[0138] Example 5

[0139] The difference between this embodiment and Embodiment 1 is that:

[0140] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture. In step (S.4), a high-frequency, high-voltage current of 4A is applied to the surface of the PVC white film after sanding in step (S.3) using a corona treatment machine to perform corona discharge, resulting in a surface tension of 36 mN / m for the corona-treated PVC white film. All other steps are the same as in Embodiment 1.

[0141] Example 6

[0142] The difference between this embodiment and Embodiment 1 is that:

[0143] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture. In step (S.4), a high-frequency, high-voltage current of 8A is applied to the surface of the PVC white film after sanding in step (S.3) using a corona treatment machine to perform corona discharge, resulting in a surface tension of 40 mN / m for the corona-treated PVC white film. All other steps are the same as in Embodiment 1.

[0144] Example 7

[0145] The difference between this embodiment and Embodiment 1 is that:

[0146] This embodiment provides a method for manufacturing stone-plastic flooring with 3D wood texture. In step (S.4), a high-frequency, high-voltage electric discharge at a discharge rate of 15 m / min is applied to the surface of the sanded PVC white film from step (S.3) using a corona treatment machine. All other steps are the same as in Embodiment 1.

[0147] Example 8

[0148] The difference between this embodiment and Embodiment 1 is that:

[0149] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture. In step (S.4), a high-frequency, high-voltage electric discharge at a discharge rate of 22 m / min is applied to the surface of the sanded PVC white film from step (S.3) using a corona treatment machine. All other steps are the same as in Example 1.

[0150] Example 9

[0151] The difference between this embodiment and Embodiment 1 is that:

[0152] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture. In step (S.4), a corona treatment machine is used to apply high-frequency, high-voltage electricity to the surface of the sanded PVC white film from step (S.3) to perform corona discharge, ensuring that the distance between the PVC white film surface and the discharge electrode to which the high-frequency, high-voltage electricity is applied is 2 cm. All other steps are the same as in Embodiment 1.

[0153] Example 10

[0154] The difference between this embodiment and Embodiment 1 is that:

[0155] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture. In step (S.4), a corona treatment machine is used to apply high-frequency, high-voltage electricity to the surface of the sanded PVC white film from step (S.3) to perform corona discharge, ensuring that the distance between the PVC white film surface and the discharge electrode to which the high-frequency, high-voltage electricity is applied is 5 cm. All other steps are the same as in Embodiment 1.

[0156] Example 11

[0157] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture, including the following steps:

[0158] (S.1) The raw materials and additives constituting the SPC substrate are added to the main extruder, the raw materials and additives constituting the substrate are melted by the main extruder and extruded into the main channel of the die, and then extruded from the die to form an SPC substrate layer.

[0159] (S.2) A PVC white film with a thickness of 0.05 mm (softening temperature of 70°C) constituting the base color layer is unwound and rolled together online with the SPC substrate layer obtained in step (S.1) to obtain an SPC substrate layer with the surface covered by the PVC white film; (S.3) The surface of the PVC white film is sanded using a belt sander (240 mesh) so that the surface roughness Ra value of the sanded PVC white film is 0.6 μm;

[0160] (S.4) A high-frequency high-voltage electric current of 6A and 30m / min is applied to the surface of the PVC white film after sanding in step (S.3) using a corona treatment machine to perform corona discharge, so that the surface tension of the PVC white film after corona treatment is 38mN / m.

[0161] (S.5) Apply a primer to the surface of the corona-treated PVC white film obtained in step (S.4), using 10 g / m² of primer. 2 Then, the primer is irradiated with 160w / cm ultraviolet light generated by a medium-pressure Hg lamp to cure the primer and obtain the primer layer.

[0162] (S.6) The primer layer obtained in step (S.5) is coated from bottom to top with a color paint, an ink to form a pattern layer, a paint or coating to form a three-dimensional wood grain layer, and a topcoat to protect the three-dimensional wood grain layer, thereby forming a color paint layer, a pattern layer, a three-dimensional wood grain layer, and a topcoat layer in sequence. The amount of color paint used is 15 g / m². 2 Then, it is irradiated with 160w / cm ultraviolet light generated by a medium-pressure Hg lamp, and the amount of ink used to form the pattern layer is 6g / m². 2 The amount of paint used to form the three-dimensional wood grain layer is 100g / m². 2 The amount of topcoat used is 10g / m². 2 .

[0163] This embodiment also provides a stone-plastic floor with a 3D wood texture prepared by the method described above.

[0164] Example 12

[0165] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture, including the following steps:

[0166] (S.1) The raw materials and additives constituting the SPC substrate are added to the main extruder, the raw materials and additives constituting the substrate are melted by the main extruder and extruded into the main channel of the die, and then extruded from the die to form an SPC substrate layer.

[0167] (S.2) A PVC white film with a thickness of 0.15 mm (with a softening temperature of 85°C) constituting the base color layer is unwound and rolled together online with the SPC substrate layer obtained in step (S.1) to obtain an SPC substrate layer with the surface covered by the PVC white film; (S.3) The surface of the PVC white film is sanded using a belt sander (with a belt mesh of 240 mesh) so that the surface roughness Ra value of the sanded PVC white film is 0.6 μm;

[0168] (S.4) A high-frequency high-voltage electric current of 6A and 30m / min is applied to the surface of the PVC white film after sanding in step (S.3) using a corona treatment machine to perform corona discharge, so that the surface tension of the PVC white film after corona treatment is 38mN / m.

[0169] (S.5) Apply a primer to the surface of the corona-treated PVC white film obtained in step (S.4), using 15 g / m² of primer. 2 Then, the primer is irradiated with 160w / cm ultraviolet light generated by a medium-pressure Hg lamp to cure the primer and obtain the primer layer.

[0170] (S.6) From bottom to top, the surface of the primer layer obtained in step (S.5) is coated with a color paint, an ink to form a pattern layer, a paint or coating to form a three-dimensional wood grain layer, and a topcoat to protect the three-dimensional wood grain layer, thereby forming a color paint layer, a pattern layer, a three-dimensional wood grain layer, and a topcoat layer in sequence. The amount of color paint used is 25 g / m². 2 Then, it is irradiated with 160w / cm ultraviolet light generated by a medium-pressure Hg lamp, and the amount of ink used to form the pattern layer is 10g / m². 2 The amount of paint or coating used to form the three-dimensional wood grain layer is 220g / m². 2 The amount of topcoat used is 15g / m². 2 .

[0171] This embodiment also provides a stone-plastic floor with a 3D wood texture prepared by the method described above.

[0172] Example 13

[0173] The difference between this embodiment and Embodiment 1 is that:

[0174] This embodiment provides a method for manufacturing SPC flooring with a 3D wood grain texture. In step (S.2), PVC raw materials and additives constituting the base color layer are added to an auxiliary extruder. The PVC raw materials and additives constituting the base color layer are melted in the auxiliary extruder and extruded into the auxiliary flow channel of the die. Then, they diffuse in the co-extrusion casting space of the die, coating the SPC substrate layer. After heat exchange through the cooling flow channel plate in the die, the material solidifies and sets, and finally, it is extruded from the die to obtain an SPC substrate layer with the base color film covering its surface. Everything else is the same as in Example 1.

[0175] Example 14

[0176] The difference between this embodiment and Embodiment 1 is that:

[0177] This embodiment provides a method for manufacturing stone plastic flooring with a 3D wood texture. In step (S.2), after the SPC substrate is extruded, its surface is coated with one or more layers of white paint, thereby obtaining an SPC substrate layer with a white paint-covered surface. Everything else is the same as in Example 1.

[0178] Example 15

[0179] The difference between this embodiment and Embodiment 1 is that:

[0180] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture. In step (S.3), a soft cloth or soft brush is used to wipe the surface of the PVC white film with an organic solvent such as acetone, resulting in a surface roughness Ra value of 0.6 μm. All other steps are the same as in Example 1.

[0181] Example 16

[0182] The difference between this embodiment and Embodiment 1 is that:

[0183] This embodiment provides a method for manufacturing stone-plastic flooring with a 3D wood texture. In step (S.4), a 400W carbon dioxide laser is used to apply a laser beam to the surface of the sanded PVC white film from step (S.3) for heat treatment. All other steps are the same as in Embodiment 1.

[0184] Comparative Example 1

[0185] The difference between this embodiment and Embodiment 1 is that:

[0186] This embodiment provides a method for manufacturing stone-plastic flooring with a 3D wood texture. In step (S.3), the abrasive belt is 100 mesh, resulting in a surface roughness Ra value of 3.2 μm for the sanded PVC white film. Everything else is the same as in Example 1.

[0187] Comparative Example 2

[0188] The difference between this embodiment and Embodiment 1 is that:

[0189] This embodiment provides a method for manufacturing stone-plastic flooring with a 3D wood texture. In step (S.3), the abrasive belt is 400 mesh, resulting in a surface roughness Ra value of 0.1 μm for the sanded PVC white film. Everything else is the same as in Example 1.

[0190] Comparative Example 3

[0191] The difference between this embodiment and Embodiment 1 is that:

[0192] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture. In step (S.4), a high-frequency, high-voltage current of 2A is applied to the surface of the PVC white film after sanding in step (S.3) using a corona treatment machine to perform corona discharge, resulting in a surface tension of 34 mN / m for the corona-treated PVC white film. All other steps are the same as in Embodiment 1.

[0193] Comparative Example 4

[0194] The difference between this embodiment and Embodiment 1 is that:

[0195] This embodiment provides a method for manufacturing stone plastic flooring with 3D wood texture. In step (S.4), a high-frequency, high-voltage current of 10A is applied to the surface of the PVC white film after sanding in step (S.3) using a corona treatment machine to perform corona discharge, resulting in a surface tension of 42 mN / m for the corona-treated PVC white film. All other steps are the same as in Embodiment 1.

[0196] [Performance Testing]

[0197]

Warpage Test

[0198] Fifty pieces of 3D wood-textured stone-plastic flooring panels were produced in batches according to the methods described in Examples 1-16 and Comparative Examples 1-4, respectively. Each panel was then cut into 240mm × 240mm samples, and the initial warpage and thermal warpage of the panels were measured. The testing procedure was as follows: The panels were placed on top of an aluminum plate with the 3D wood grain layer facing upwards and kept at 23±2℃ and 50±5%RH for 24 hours. The average initial warpage of the panel samples was measured using calipers. The temperature in the constant temperature drying oven was adjusted to 80℃, and the panel samples, along with the aluminum plate, were placed in the oven for 6 hours. The panel samples, along with the aluminum plate, were then removed and kept at 23±2℃ and 50±5%RH for 24 hours. The average thermal warpage of the panel samples was measured using calipers. The test results are shown in Table 1 below.

[0199] Table 1

[0200]

[0201]

[0202] [Immersion Peel Strength Test]

[0203] 3D wood-textured SPC flooring panels were prepared according to the methods described in Examples 1-16 and Comparative Examples 1-4, respectively. The panels were tested for their immersion peel strength according to the relevant content of GB / T17657-2013 "Test Methods for Physical and Chemical Properties of Wood-based Panels and Decorative Wood-based Panels". The immersion peel strength test method was as follows: Samples with a length of 75mm and a width of 75mm were cut from the panels. Each sample was immersed in boiling water at 100℃ for 4 hours, then dried in a drying oven at 63℃ for 20 hours. The samples were then immersed in boiling water at 100℃ for 4 hours, then dried in a drying oven at 63℃ for 3 hours. The samples were completely submerged in boiling water during immersion. Careful observation was conducted to check for peeling and delamination between the paint layers and the SPC substrate layer. The length of the peeled or delaminated portion of each paint layer on each side of the sample was measured using a steel ruler. If the peeling or delamination on one side was divided into several segments, these segments were accumulated. The test results are shown in Table 2 below.

[0204] Table 2

[0205] Group Length (mm) of peeling or delamination on each edge of each paint layer of the sample Example 1 3.5 Example 2 7.5 Example 3 7.0 Example 4 6.5 Example 5 6.0 Example 6 5.5 Example 7 6.4 Example 8 6.3 Example 9 7.1 Example 10 6.2 Example 11 7.6 Example 12 7.5 Example 13 5.6 Example 14 5.8 Example 15 5.7 Example 16 7.8 Comparative Example 1 8.2 Comparative Example 2 7.6 Comparative Example 3 7.9 Comparative Example 4 7.8

[0206] Analysis of the data in Tables 1 and 2 shows that sanding the surface of the PVC white film using a belt sander (240 mesh) resulted in a surface roughness Ra of 0.6 μm. Then, applying a 6A current at a discharge rate of 30 m / min with a 4cm distance between the PVC white film surface and the discharge electrode using a corona treatment machine significantly improved the surface tension of the PVC white film, reducing it to 38 mN / m. The shortest length of peeling or delamination on each edge of the prepared 3D wood grain stone-plastic flooring was 3.5 mm. This indicates that the adhesion between the PVC white film and the SPC substrate layer, as well as the 3D wood grain layer above the SPC substrate layer, was enhanced after sanding and corona treatment, resulting in more stable bonding and effectively reducing the warpage of the 3D wood grain layer.

[0207] The above description is merely a detailed explanation of preferred embodiments and principles of the present invention. For those skilled in the art, there may be changes in specific implementation methods based on the ideas provided by the present invention, and these changes should also be considered within the scope of protection of the present invention.

Claims

1. A method for manufacturing stone plastic flooring with 3D wood texture, characterized in that, At least the following steps are included: (S.1) The step of extruding to obtain the stone-plastic flooring substrate; (S.2) The step of covering the surface of the stone plastic flooring substrate with a base color layer; (S.3) The step of giving the surface of the base color layer irregularly distributed pores; (S.4) The step of stimulating the surface of the base color layer obtained in the previous step with a high-energy beam; (S.5) The step of applying a primer to at least a portion of the surface of the base color layer obtained in the previous step, and curing the primer to obtain a primer layer; (S.6) The step of forming a color paint layer, a pattern layer, a three-dimensional wood grain layer and a topcoat layer sequentially from bottom to top on at least a portion of the surface of the primer layer.

2. The method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1, characterized in that, The process of obtaining the base color layer in step (S.2) includes the step of covering the surface of the stone plastic flooring substrate with a base color film.

3. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1 or 2, characterized in that, The base color layer includes at least one or a combination of polyvinyl chloride resin, colorant, plasticizer, heat stabilizer, and lubricant.

4. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1 or 2, characterized in that, The base color layer is white and has a thickness of 0.05 to 0.15 mm.

5. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1, characterized in that, The process of giving the surface of the base color layer irregularly distributed holes in step (S.3) includes the step of bringing the surface of the base color layer into contact with the abrasive and thus polishing it.

6. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 5, characterized in that, The surface roughness Ra value of the base color layer after contact with the abrasive is 0.3 to 1.6 μm.

7. A method for manufacturing stone-plastic flooring with 3D wood grain texture according to claim 5, characterized in that, The abrasive tool can be any one of a belt sander, a belt grinder, or a belt polisher.

8. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 5 or 6, characterized in that, The abrasive tool includes one or more of the following: abrasive belt, abrasive paper, and gauze.

9. A method for manufacturing stone-plastic flooring with 3D wood grain texture according to claim 1, characterized in that, The process of subjecting the surface of the base color layer to high-energy beam stimulation in step (S.4) includes the step of subjecting the surface of the base color layer to high-frequency high-voltage corona discharge.

10. A method for manufacturing stone-plastic flooring with 3D wood grain texture according to claim 9, characterized in that, The current magnitude of the high-frequency high-voltage corona discharge is 4–8 A.

11. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1 or 9, characterized in that, The surface tension of the base color layer after being stimulated by a high-energy beam is 36–40 mN / m.

12. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1 or 9, characterized in that, This results in the surface of the base color layer being subjected to a high-frequency, high-voltage corona discharge rate of 15–30 m / min.

13. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 9 or 10, characterized in that, The distance between the surface of the base color layer and the discharge electrode to which high-frequency high-voltage electricity is applied is 2 to 5 cm.

14. A method for manufacturing stone-plastic flooring with 3D wood grain texture according to claim 1, characterized in that, The primer in step (S.5) includes at least a photocrosslinking resin and a photoinitiator.

15. A method for manufacturing stone-plastic flooring with 3D wood grain texture according to claim 14, characterized in that, The photocrosslinking resin includes any one or more combinations of unsaturated polyester, epoxy resin, acrylic resin, acrylic-modified polyurethane resin, acrylic-modified silicone resin, acrylic-modified epoxy resin, waterborne epoxy acrylate, waterborne polyurethane acrylate, and waterborne polyester acrylic.

16. A method for manufacturing stone-plastic flooring with 3D wood grain texture according to claim 14, characterized in that, The photoinitiator includes any one of the following: free radical polymerization initiator, cationic polymerization initiator, energy transfer initiator, and ionic reaction initiator.

17. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1 or 14, characterized in that, In step (S.5), the amount of primer applied to the surface of the base coat is 10-15 g / m². 2 .

18. A method for manufacturing stone-plastic flooring with 3D wood grain texture according to claim 1, characterized in that, The paint layer in step (S.6) is white, and the amount of paint used in the paint layer is 15-25 g / m³. 2 .

19. A method for manufacturing stone-plastic flooring with 3D wood grain texture according to claim 1, characterized in that, The process of forming the pattern layer in step (S.6) includes: applying ink to at least a portion of the surface of the paint layer to form a wood grain pattern, and then curing it to obtain the pattern layer.

20. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1 or 19, characterized in that, In step (S.6), the amount of ink used in the pattern layer is 6-10 g / m². 2 .

21. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1, characterized in that, The process of forming the three-dimensional wood grain layer in step (S.6) includes the step of covering at least a portion of the surface of the pattern layer with a three-dimensional wood grain layer having a three-dimensional structure.

22. A method for manufacturing stone-plastic flooring with 3D wood grain texture according to claim 1, characterized in that, The process of forming the topcoat layer in step (S.6) includes the steps of coating at least a portion of the surface of the three-dimensional wood grain layer with topcoat and curing it to obtain the topcoat layer.

23. A method for manufacturing stone-plastic flooring with 3D wood texture according to claim 1 or 22, characterized in that, In step (S.6), the amount of topcoat used in the topcoat layer is 10-15 g / m². 2 .

24. A stone plastic floor with 3D wood texture prepared by the method of any one of claims 1 to 23.

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