Teak surface treatment process

Abstract

The invention belongs to the technical field of furniture manufacturing, and particularly relates to a teak surface treatment process which realizes accurate control and durability breakthrough on teak surface chromatic aberration through the synergistic effect of a four-stage polishing system and a three-layer primer system in combination with a two-color regulation and control technology and intelligent drying management. According to the technology, through the industrial process of'four-grinding, three-bottom, two-color and one-surface ', the aesthetic presentation and long-acting protection requirements are balanced, the contradiction of cost-attractiveness-maintenance period of a traditional technology is broken through, and a solution with both standardized production and lasting decoration effect is provided for high-end outdoor teak furniture.

Description

Technical Field

[0001] The present invention belongs to the technical field of furniture manufacturing, and particularly relates to a teak surface treatment process. Background Art

[0002] At present, teak, as a high-end furniture material, has dual advantages with its excellent physical properties (density 0.65 - 0.85 g / cm 3 , compressive strength > 55 MPa) and unique aesthetic value. However, its surface color difference problem is particularly prominent in outdoor exposure scenarios. Research shows that flavonoid pigments in teak heartwood will undergo photo-oxidation reactions under the action of UV-B radiation (daily average dose > 5 kJ / m 2 ), and the breakage of the benzene ring structure leads to the change of hue from golden yellow to grayish brown (ΔE*ab > 3.0). At the same time, tannic acid combines with iron ions in rainwater to form dark complexes, further exacerbating the color difference phenomenon.

[0003] Traditional surface treatment processes face the contradiction between protection and ornamental value: thick coatings can provide protection but cover the natural texture, while thin coatings retain the beauty but have a high UV transmittance. What's more difficult is that it is hard to balance process efficiency and durability. With the special influence of furniture splicing processes and carved hollow structures - dust is likely to accumulate in grooves, accelerating the photochemical reaction, and the corrosion of metal connectors spreads iron ions to form a catalytic effect, resulting in significant color differences in teak furniture after treatment within only 3 - 4 months outdoors, requiring frequent maintenance, which greatly increases the usage cost.

[0004] The existing teak surface treatment processes need to be further improved to simultaneously meet the three requirements of aesthetic presentation, long-term protection, and reasonable maintenance cycle. Summary of the Invention

[0005] The purpose of the present invention is to overcome the problem that teak furniture treated by traditional processes is prone to fading, and to provide a teak surface treatment process.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A teak surface treatment process includes the following steps: primary sanding, using primary sanding tools to sand the teak surface to remove fine hairs in the wood grain; primary primer spraying, using basic primer to spray the teak surface twice and drying it in a preset environment and for a preset time after spraying; secondary primer spraying, using basic primer to spray the teak surface twice and drying it in a preset environment and for a preset time after spraying; pre-applying colored paint, using basic colored paint for partial rubbing to balance color differences; tertiary primer spraying, using reinforced primer to spray the teak surface twice and drying it within a preset time; tertiary sanding, using secondary sanding tools to sand the teak to remove surface particles; spraying colored paint, using reinforced colored paint to spray the teak surface and drying it within a preset time; quaternary sanding, using tertiary sanding tools to sand the teak surface to remove surface particles; spraying topcoat, using topcoat to coat the teak surface and drying it within a preset time.

[0008] The teak surface treatment process of the present invention, through the synergistic effect of a four-stage sanding system (primary grinding to remove fine hairs in the wood grain - secondary grinding to eliminate newly emerging fibers - tertiary grinding to remove coating particles - final grinding to optimize surface accuracy) and a three-layer primer system (basic sealing layer to block pigment migration - enhanced adhesion layer to improve mechanical bite - durable reinforcement layer to build an anti-aging barrier), combined with a two-color regulation technology (pre-coloring to correct natural color differences + final coloring to standardize the decorative color layer) and intelligent drying management (phased temperature and humidity control to avoid coating defects), achieves precise control of the color difference on the teak surface (ΔE*ab value stable < 1.5, no color change after 8 months of outdoor exposure) and a breakthrough in durability (60% improvement in anti-ultraviolet aging performance, maintenance cycle extended to more than 12 months). Through the industrialized process of "4 grinding - 3 priming - 2 coloring - 1 coating", this process not only balances the aesthetic presentation and long-term protection requirements, but also breaks through the contradiction of cost - aesthetics - maintenance cycle in traditional processes, providing a solution with both standardized production and long-lasting decorative effects for high-end outdoor teak furniture.

[0009] Further, the drying time for the first primer spray is n, the drying times for the second and third primer sprays are 8n, the drying time for the colored paint spray is 4n, and the drying time for the topcoat spray is 48n, where n is 1. In this solution, the progressive design of the drying time (1 hour → 8 hours → 8 hours → 4 hours → 48 hours) not only ensures the full curing of each layer of paint but also avoids unnecessary process waiting times. The relatively short drying time (1 hour) after the initial spray allows for a quick transition to the next process, while the drying times for subsequent sprays gradually increase to ensure the coating quality. The longer drying times for the second and third primer sprays ensure the full penetration and curing of the second and third layers of primer, enhancing the adhesion and surface flatness of the coating. The moderate drying time for the colored paint spray ensures the uniform curing of the colored paint, balances color differences, and at the same time avoids overly extending the process cycle. The longest drying time for the topcoat spray ensures the complete curing of the topcoat, forming a hard and durable protective layer, providing the final aesthetics and anti-aging performance.

[0010] Further, the primary sanding tool is a 240-mesh nylon-patterned abrasive head, the secondary sanding tool is a 320-mesh nylon-patterned abrasive head, and the tertiary sanding tool is a 400-mesh fine sandpaper. By gradually increasing the mesh number of the sanding tools, the present invention ensures a progressive process of surface treatment from coarse to fine, which not only improves the adhesion of the coating but also retains the natural texture and aesthetics of teak.

[0011] Further, the base primer is prepared by mixing a curing agent, a colorant, and a polyurethane acrylate in a ratio of 0.8:1.2:1. The ratio design of this solution ensures the uniformity and stability of the primer. The curing agent provides rapid curing, the colorant enhances fluidity, and the polyurethane acrylate provides good adhesion and durability.

[0012] Further, the preset drying conditions are 25°C and 70% relative humidity, and the drying time is 1 hour. Drying under constant temperature and humidity conditions ensures the full curing of the primer and avoids coating quality problems caused by environmental changes.

[0013] Further, in the first primer spray step, the spraying amount of the base primer is 100 - 120 grams per square meter each time. In the second and third primer spray steps, the spraying amount of the base primer is reduced to 80 - 120 grams per square meter each time. By adjusting the amount in stages, this solution provides sufficient sealing and basic adhesion during the initial spray, while subsequent sprays enhance the permeability and adhesion of the coating by appropriately reducing the amount, avoiding adhesion problems caused by overly thick coatings. For teak furniture with complex structures such as carving and hollowing, adjusting the amount in stages can better adapt to the spraying requirements of different parts, ensure uniform coating coverage, and avoid paint accumulation or missed coating phenomena.

[0014] Further, in the step of pre-coating with colored paint, the base colored paint is prepared by mixing a slow-drying agent and a color-tuning paint in a ratio of 1:1. In this solution, the slow-drying agent extends the drying time of the colored paint, facilitating local rubbing and color adjustment, and the color-tuning paint ensures uniform color. It should be noted that the slow-drying agent in this solution is slow-drying water.

[0015] Further, in the step of spraying colored paint, the reinforced colored paint is prepared by mixing a curing agent, a blending agent, and colored paint, and the ratio of the curing agent, the blending agent, and the colored paint is 0.5:1.8:1.

[0016] Further, the amount of the reinforced colored paint used is 60 - 90 grams per square meter. This ratio ensures the uniformity and stability of the reinforced colored paint. The curing agent provides rapid curing, the blending agent enhances fluidity, and the acrylic provides good adhesion and durability.

[0017] Further, in the step of spraying the topcoat, the topcoat is prepared by mixing a curing agent, a blending agent, and polyurethane acrylate, and the ratio of the three is 0.5:1:1, with an amount of 60 - 90 grams per square meter. This ratio ensures the uniformity and stability of the topcoat. The curing agent provides rapid curing, the blending agent enhances fluidity, and polyurethane acrylate provides good adhesion and durability.

[0018] Further, the ratio of the primer amounts for the first primer spraying, the second primer spraying, and the third primer spraying is 5:4:4. Description of the Drawings

[0019] Figure 1 is a flowchart of the present invention. Detailed Embodiments

[0020] The following describes the detailed embodiments of the present invention with reference to the drawings. In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0021] The present invention discloses a teak surface treatment process, including the following steps:

[0022] First sanding, using a primary sanding tool to sand the teak surface to remove fine hairs in the wood grain;

[0023] That is, initial sanding, using a coarse-grained sanding tool to remove the fine hairs in the wood grain and construct a primer adhesion base surface.

[0024] Primary primer spraying: Use the base primer to spray the surface of the axle wood twice, and dry it in a preset environment and for a preset time. When spraying, adopt the cross-spraying method. For example, if the first spray is horizontal, the second spray is vertical; or the first spray is vertical and the second spray is horizontal.

[0025] That is, the base sealing layer: Through two sprays of the base primer, block the pigment migration channels.

[0026] Secondary primer spraying: Use the base primer to spray the surface of the axle wood twice, and dry it in a preset environment and for a preset time.

[0027] That is, the strengthening adhesion layer: Through 1.5 overlays of the base primer, improve the mechanical bite of the coating.

[0028] Secondary grinding: Use primary grinding tools to grind the axle wood to remove the newly erected fine hairs.

[0029] That is, use fine-grained tools for secondary grinding to eliminate the newly raised fibers and ensure the surface flatness.

[0030] Pre-coat with colored paint: Use the base colored paint for local rubbing to balance the color difference.

[0031] That is, pre-coloring: Through local rubbing of the base color paste, correct the deviation of the natural wood color.

[0032] Tertiary primer spraying: Use the reinforced primer to spray the surface of the axle wood twice and dry it within a preset time.

[0033] That is, the durable reinforcement layer: 1.5 passes of the reinforced primer penetrate to build an anti-aging barrier. It should be noted that in this solution, the two sprays mean first spraying a complete primer on the surface of the axle wood to ensure uniform coverage. After the first spray dries, perform local supplementary spraying, focusing on areas that may not be fully covered or require additional protection.

[0034] Tertiary grinding: Use secondary grinding tools to grind the axle wood to remove the surface particles.

[0035] That is, use medium-grained tools for tertiary grinding to remove the coating particles and enhance the interlayer bonding force.

[0036] Spray colored paint: Use the reinforced colored paint to spray the surface of the teak and dry it within a preset time.

[0037] That is, evenly spray the reinforced colored paint to standardize the decorative color layer.

[0038] Quaternary grinding: Use tertiary grinding tools to grind the surface of the axle wood to remove the surface particles.

[0039] That is, use ultra-fine-grained tools for quaternary grinding to refine the surface and optimize the topcoat coating effect.

[0040] Spray the topcoat on the surface of the axle wood and dry it within a preset time;

[0041] Spray with the topcoat to provide final protection and gloss, ensuring long-term durability.

[0042] In one embodiment, the drying time for the first primer spray is n, the drying times for the second and third primer sprays are 8n, the drying time for spraying the colored paint is 4n, and the drying time for spraying the topcoat is 48n, where n is 1. In this solution, the progressive design of the drying time (1 hour → 8 hours → 8 hours → 4 hours → 48 hours) not only ensures the full curing of each layer of paint but also avoids unnecessary process waiting time. The relatively short drying time (1 hour) after the initial spray allows for a quick transition to the next process, while the drying times for subsequent sprays gradually increase to ensure the coating quality. The longer drying times for the second and third primer sprays ensure that the second and third layers of primer fully penetrate and cure, enhancing the adhesion and surface flatness of the coating. The moderate drying time for spraying the colored paint ensures the uniform curing of the colored paint, balances color differences, and at the same time avoids over-extending the process cycle. The longest drying time for spraying the topcoat ensures the complete curing of the topcoat, forming a hard and durable protective layer, providing the final aesthetics and anti-aging performance.

[0043] In one embodiment, the primary grinding tool is a 240-mesh nylon-patterned grinding head, the secondary grinding tool is a 320-mesh nylon-patterned grinding head, and the tertiary grinding tool is a 400-mesh fine sandpaper. The present invention ensures a progressive process of surface treatment from rough to fine by gradually increasing the mesh number of the grinding tools, which not only improves the adhesion of the coating but also retains the natural texture and aesthetics of the teak.

[0044] In one embodiment, the base primer is prepared by mixing a curing agent, a blending agent, and polyurethane acrylate in a ratio of 08:1.2:1. The ratio design of this solution ensures the uniformity and stability of the primer. The curing agent provides rapid curing, the blending agent enhances fluidity, and polyurethane acrylate provides good adhesion and durability.

[0045] In one embodiment, the preset drying conditions are 25°C and 70% relative humidity, and the drying time is 1 hour. Drying under constant temperature and humidity conditions ensures the full curing of the primer and avoids coating quality problems caused by environmental changes.

[0046] In one embodiment, in a primary primer spraying step, the spraying amount of the base primer is 100 - 120 grams per square meter each time. In the secondary primer spraying step and the tertiary primer spraying step, the spraying amount of the base primer is reduced to 80 - 120 grams per square meter each time. By adjusting the amount in stages in this solution, the initial spraying provides sufficient sealing and basic adhesion, while subsequent sprayings enhance the permeability and adhesion of the coating by appropriately reducing the amount, avoiding the problem of decreased adhesion caused by an overly thick coating. For teak furniture with complex structures such as carving and hollowing, adjusting the amount in stages can better adapt to the spraying requirements of different parts, ensure uniform coating coverage, and avoid paint accumulation or missed coating.

[0047] In one embodiment, in the step of pre - applying colored paint, the base colored paint is prepared by mixing a retarder and a color - matching paint in a ratio of 1:1. In this solution, the retarder extends the drying time of the colored paint, facilitating local wiping and color adjustment, and the color - matching paint ensures uniform color. It should be noted that the retarder in this solution is slow - drying water.

[0048] In one embodiment, in the step of spraying colored paint, the reinforced colored paint is prepared by mixing a curing agent, a blending agent, and colored paint, and the ratio of the curing agent, the blending agent, and the colored paint is 1:1.8:1. The spraying amount of the reinforced colored paint is 60 - 90 grams per square meter. This ratio ensures the uniformity and stability of the reinforced colored paint. The curing agent provides rapid curing, the blending agent enhances fluidity, and the acrylic provides good adhesion and durability. Preferably, the colored paint is a semi - transparent coloring paint. Further, the colored paint is adjusted by acrylic and color - matching paint.

[0049] In one embodiment, in the step of spraying topcoat, the topcoat is prepared by mixing a curing agent, a blending agent, and polyurethane acrylate, and the ratio of the three is 0.5:1:1, with a spraying amount of 60 - 90 grams per square meter. This ratio ensures the uniformity and stability of the topcoat. The curing agent provides rapid curing, the blending agent enhances fluidity, and polyurethane acrylate provides good adhesion and durability.

[0050] In one embodiment, the primer spraying amounts of the primary primer spraying, secondary primer spraying, and tertiary primer spraying are in a ratio of 5:4:4.

[0051] The technical solution of the present invention effectively solves the problem of color difference on the teak surface and improves durability through multiple sanding, primer spraying, pre-coating with colored paint, and topcoat spraying. The multiple sanding includes: the first sanding to remove the fine hairs in the wood grain and provide a flat surface for primer spraying; the second sanding to remove the newly erected fine hairs and ensure a smooth surface; the third sanding to remove the surface particles and improve the coating adhesion; the fourth sanding to further refine the surface and provide an ideal base for topcoat spraying. The primer spraying is divided into: the first primer spraying uses the basic primer for 2 sprays to seal the wood surface and prevent uneven penetration of subsequent coatings; the second primer spraying uses the basic primer for 2 sprays to enhance the coating adhesion and provide better surface flatness; the third primer spraying uses the reinforced primer for 2 sprays to further reinforce the coating and improve durability. The pre-coating with colored paint balances the color difference and reduces the color difference problem by locally wiping the basic colored paint; the spraying of colored paint uses the reinforced colored paint for spraying to evenly cover the surface and enhance the aesthetics. The topcoat spraying uses the topcoat for spraying to provide the final protection and gloss and ensure long-term durability. The control of the drying environment and time is an important optimization point of the present invention. By standing and drying in a preset environment and at preset times in stages, the full curing and stability of each layer of coating are ensured. This staged drying method avoids cracking or decreased adhesion of the coating caused by too fast drying, and at the same time ensures the uniformity and stability of the coating, significantly improving durability and anti-aging performance. In addition, the preset drying environment further optimizes the curing effect of the coating, reduces the interference of environmental factors on the coating quality, and enables teak furniture to still maintain excellent aesthetics and functionality in complex outdoor environments. Compared with the prior art, the present invention realizes through the "4 sanding - 3 primer - 2 color - 1 topcoat" process chain: (1) color difference control, pre-coloring technology + multi-layer sealing system, ΔE*ab value stable < 1.5 (8 months of outdoor exposure); (2) durability breakthrough, the synergistic effect of reinforced primer + topcoat, the anti-ultraviolet aging performance is improved by 60%; (3) maintenance optimization: the coating density is increased, and the maintenance cycle is extended to more than 12 months; (4) drying process innovation: dynamic regulation of environmental parameters, so that the coating adhesion reaches the first-level standard (ASTM D3359). Taking into account aesthetic protection and long-term durability, it breaks through the triple contradiction of cost - aesthetics - maintenance cycle of traditional processes, and can ensure that the teak surface will not change color or fade within 8 months outdoors, thus reducing the number of maintenance times.

[0052] According to the disclosure and teachings of the above specification, those skilled in the art to which the present invention pertains can also make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention.

Claims

1. A teak surface treatment process, characterized in that, It includes the following steps: Primary grinding: Use a primary grinding tool to grind the surface of the axle wood to remove the fine hairs in the wood grain. First primer spraying: Use a basic primer to spray the surface of the axle wood twice, and dry it in a preset environment and for a preset time after spraying. Second primer spraying: Use a basic primer to spray the surface of the axle wood twice, and dry it in a preset environment and for a preset time after spraying. Secondary grinding: Use a primary grinding tool to grind the axle wood to remove the newly erected fine hairs. Pre-coating with colored paint: Use a basic colored paint for partial rubbing to balance the color difference. Third primer spraying: Use a reinforced primer to spray the surface of the axle wood twice, and dry it within a preset time. Third grinding: Use a secondary grinding tool to grind the axle wood to remove the particles on the surface. Spraying colored paint: Use a reinforced colored paint to spray the surface of the teak wood, and dry it within a preset time. Fourth grinding: Use a tertiary grinding tool to grind the surface of the axle wood to remove the particles on the surface. Spraying topcoat: Use a topcoat to spray the surface of the axle wood, and dry it within a preset time.

2. The teak surface treatment process according to claim 1, wherein, The drying time for the first primer spraying is n, the drying times for the second and third primer sprayings are 8n, the drying time for spraying colored paint is 4n, and the drying time for spraying topcoat is 48n, where n is 1.

3. The teak surface treatment process according to claim 1, characterized in that, The primary grinding tool is a 240-mesh nylon-patterned grinding head, the secondary grinding tool is a 320-mesh nylon-patterned grinding head, and the tertiary grinding tool is a 400-mesh fine sandpaper.

4. The teak surface treatment process according to claim 1, characterized in that, The basic primer is prepared by mixing a curing agent, a blending agent, and polyurethane acrylate in a ratio of 0.8:1.2:

1.

5. The teak surface treatment process according to claim 1, characterized in that, The preset drying conditions are 25°C and 70% relative humidity, and the drying time is 1 hour.

6. The teak surface treatment process according to claim 1, characterized in that, In the first primer spraying step, the spraying amount of the basic primer is 100 - 120 grams per square meter each time. In the second and third primer spraying steps, the spraying amount of the basic primer is reduced to 80 - 120 grams per square meter each time.

7. The teak surface treatment process according to claim 1, characterized in that, In the step of pre-coating with colored paint, the basic colored paint is prepared by mixing a slow-drying agent and a color-tuning paint in a ratio of 1:

1.

8. The teak surface treatment process according to claim 1, characterized in that, In the step of spraying colored paint, the reinforced colored paint is prepared by mixing a curing agent, a blending agent, and a colored paint, and the ratio of the curing agent to the colored paint is 1:1.8:

1. The usage amount of the reinforced colored paint is 60 - 90 grams per square meter.

9. The teak surface treatment process according to claim 1, characterized in that, In the step of spraying topcoat, the topcoat is prepared by mixing a curing agent, a blending agent, and polyurethane acrylate in a ratio of 0.5:1:1, and the usage amount is 60 - 90 grams per square meter.

10. The teak surface treatment process according to claim 1, characterized in that, The primer usage ratios for the first, second, and third primer sprayings are 5:4:4.

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