Teak batten and manufacturing method thereof

Abstract

The present disclosure provides a method of manufacturing a teak batten. The method comprises the following steps: (a) peeling a teak log to form a plurality of main veneers; (b) repairing a defect area on the main single board by using a corresponding high-quality secondary single board to obtain a defect-free main single board; (c) combining each main veneer longitudinally and / or transversely using scarf joint, and bonding two or more main veneers together by an adhesive to form a plurality of combined veneers; (d) longitudinally cutting each combined veneer in the longitudinal direction to form a plurality of strips; (e) compressing the laminated strip at high pressure by an adhesive to form a multi-layer block; (f) longitudinally cutting the multi-layer block for a plurality of times to form a plurality of teak battens with required thickness and width; (g) kiln-drying each teak batten until the teak batten has the required moisture; and (h) solarizing the teak strip.

Description

TECHNICAL FIELD

[0001] The present invention generally relates to a method for manufacturing teak slats and teak slats obtained by the method. BACKGROUND ART

[0002] Teak is a dense, fine-grained hardwood derived from the teak (Tectona grandis) tree native to South and Southeast Asia. Teak is originally golden in color and has a smooth grain and texture. The natural anti-microbial and insecticidal substances in teak provide excellent natural anti-corrosion and weather resistance, even without treatment. This precious wood is suitable for shipbuilding: due to the superior durability of teak, teak is used in the shipbuilding industry to construct artificial teak decks for yachts and sailboats.

[0003] Only four countries in the world have natural teak forests: India, Laos, Myanmar, and Thailand. Myanmar is the only country that supplies teak from natural forests to the international market. The global teak supply from natural and planted teak forests is between 2 million cubic meters and 2.5 million cubic meters, accounting for approximately 2% of the total tropical roundwood production. The global supply of teak from natural forests is declining at an alarming rate of approximately 1.3% per year, while planted teak has shown an increasing trend between 1995 and 2010, growing from 1.3 million hectares to 5.7 million hectares (Kollert and Cherubini, 2012).

[0004] Since the establishment of the world's first teak plantation in India (Nilambur-Kerala) in the 1840s, it has been a traditional practice to produce high-quality teak with a relatively long rotation period of 50 to 70 years. Due to the decreasing supply of mature natural teak, new alternative methods are being explored to reduce the dependence on natural teak. The traditional method of using natural teak to produce teak slats consists of several steps, including (i) cutting teak logs into quarter logs; (ii) resawing the quarter logs into teak boards; (iii) removing the bark and heartwood from the teak boards; (iv) ripping the teak boards into sawn timber; (v) ripping the sawn timber longitudinally in a manner that satisfies the quality requirements to obtain teak slats of the required dimensions for the production of the final product; (vi) kiln-drying the teak slats; (vii) planing the dried teak slats to remove the unevenness on the outside of the teak slats; (viii) sun-drying the planed teak slats to mature their color; (ix) removing the defects from the sun-dried teak slats; and (x) surface-treating the teak slats by various methods known in the relevant field to obtain the final teak slats with the required properties (see Figure 1).

[0005] US20070292656A1 discloses a composite board, which includes a first layer with an orientation and a second layer bonded to the first layer, wherein the second layer includes a plurality of wood veneer structures, and each wood veneer structure is substantially perpendicular to the orientation of the first layer. It also discloses a method for manufacturing a composite board, which includes providing a first layer with an orientation; combining the second layer by arranging a plurality of wood veneer structures such that each wood veneer structure is substantially perpendicular to the orientation of the first layer; and bonding the first layer to the first surface of the second layer.

[0006] CN100344425C discloses a technology for producing floors from medium or small diameter plywood, including steps such as veneering, drying, removing excess edges, milling the edges into bevels, longitudinally splicing, sanding, applying resin, laminating, pre-pressing, hot-pressing, longitudinally sawing into strips, planing, transversely splicing, planing, making tenons and mortises, painting, and polishing.

[0007] Due to the decreasing supply of teak from natural forests, teak logs with a shorter rotation period of 20 to 30 years have good prospects and are currently used for veneer and sawlog production to obtain relatively quick returns. Wood from short-rotation teak plantations is generally of lower price in the timber market because this kind of wood is considered to be of inferior quality in terms of quality attributes such as color, density, natural durability, size, and defect characteristics.

[0008] Thai Small Patent No. 14937 discloses a method for producing teak slats from artificial teak, which includes the following steps: (i) slicing teak logs to form a plurality of veneers with a thickness of 1 to 2 mm; (ii) obtaining defect-free veneers by die-cutting the defective areas from each defective veneer, filling the notched veneer with a corresponding piece of other veneer, and attaching another veneer to the notched veneer through an adhesive; (iii) laminating the defect-free veneers under high-pressure compression through an adhesive to form a multi-layer block; (iv) longitudinally cutting the block multiple times along the longitudinal direction to form a plurality of teak slats (see Figure 2). Summary of the Invention

[0009] An object of the present invention is to obtain teak slats with a straight grain pattern by a method that has fewer steps, lower costs, higher yields, and is generally more "green" and sustainable compared to existing methods for manufacturing teak slats.

[0010] One embodiment of the present invention that is well-suited to achieve the above object is a method for manufacturing teak slats, which comprises the following steps: (a) debarking teak logs to form a plurality of primary veneers; (b) obtaining defect-free primary veneers by patching the defective areas on the primary veneers with a corresponding piece of high-quality secondary veneer; (c) longitudinally and / or transversely combining each primary veneer using a scarf joint and bonding two or more primary veneers together with an adhesive to form a plurality of combined veneers; (d) longitudinally cutting each combined veneer to form a plurality of strips; (e) laminating the strips under high-pressure compression with an adhesive to form a multi-layer block; (f) longitudinally cutting the multi-layer block multiple times to form a plurality of teak slats having a desired thickness and width; and (g) kiln-drying each teak slat to have a desired moisture content. The method of the present invention can use younger trees, remove defects more effectively, and provide larger sizes similar to mature natural teak.

[0011] Another embodiment is a teak slat obtained by the above method for manufacturing teak slats, which has a straight grain pattern and a transverse coefficient of thermal expansion (CTE) of less than 50×10 -6 / °C. The teak slats of the present invention are very suitable for decking luxury ships (such as superyachts), manufacturing furniture, and other decorative items due to their durability against ultraviolet rays and salt water.

[0012] The method of the present invention is advantageous over the prior art methods. One of the main advantages is that the method of the present invention can produce longer teak slats because the method uses a scarf joint. Length is considered important in teak slat manufacturing because natural teak is becoming increasingly scarce, especially teak with a length of 2 meters or longer. This production method allows manufacturers to easily produce final teak slats with a length exceeding 4 meters using shorter teak logs (with a length of less than 2 meters). The preferred length of the teak slats produced by the method of the present invention is 4 meters because this is suitable and feasible for production and transportation. Width is also considered important. Laminating allows for wider slats, which are considered scarce nowadays. For example, it is considered rare to find natural teak with a straight grain and a width of 100 mm or more. Anything close to or exceeding 100 mm is considered wide.

[0013] Another advantage of the method of the present invention is that, compared with the prior art methods, the production speed of teak slats is faster. Part of the reason is that the method of the present invention uses veneer patching to remove defects on the veneers, rather than using die-cutting or laser to cut out defects as in the prior art methods. Veneer patching is more time-efficient compared with the previous methods. Due to lower precision requirements, the production at this stage can be twice as fast compared with the prior art.

[0014] In addition, the method of the present invention can reduce waste (increase production) and can utilize the entire length of teak logs. Existing methods rely on the length and width of teak logs.

[0015] The method of the present invention also provides teak slats with a more aesthetically pleasing "appearance". Relatively speaking, the teak slats obtained by the method of the present invention are more similar to natural teak because the method can produce thinner veneers, which in turn makes the "lines" formed by several layers of strips less conspicuous. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 shows a flowchart of a conventional method for manufacturing teak slats;

[0017] FIG. 2 shows a flowchart of a method for manufacturing teak slats disclosed in Thai Small Patent No. 14937;

[0018] Figure 3A , 3B and FIGS. 3C show a teak log ( Figure 3A ) for peeling into a main veneer, a main veneer with defects ([[]] Figure 3B ), and a main veneer patched with a corresponding number of high-quality secondary veneers ([[]] Figure 3C );

[0019] Figure 4A 4B Figure 4A , Figure 4B and FIGS. 4C show a top view of a combined veneer joined by finger jointing ([[]] Figure 4A ), a top view and a perspective view of a strip longitudinally cut from the combined veneer ([[]] Figure 4B and 4C );

[0020] Figure 5A 5B Figure 5A , Figure 5B and FIGS. 5C show a perspective view of a multi-layer block made of laminated strips ([[]] Figure 5A ), a front view of the multi-layer block showing one strip layer substantially parallel to another strip layer ([[]] Figure 5B ), and a perspective view of the multi-layer block with a longitudinal cut mark (A-A) ([[]] Figure 5C );

[0021] Figure 6

[0022] Figure 7 shows a perspective view of a teak slat obtained by the method of the present invention; and

[0022] Figure 7 shows a flowchart of a method for manufacturing teak slats according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0023] The present invention can be best understood with reference to the detailed drawings and description presented herein. Embodiments of the present invention are discussed below with reference to the drawings. However, it will be readily apparent to those skilled in the art that the detailed description given herein with respect to these drawings is for explanatory purposes, as the present invention extends beyond these limited embodiments. For example, it should be understood that those skilled in the art will recognize, in light of the teachings of the present invention, that depending on the needs of a particular application, there are various alternative and suitable ways to implement the functionality of any given detail described herein, in addition to the specific implementation choices in the embodiments described and shown below. That is, there are far too many modifications and variations of the present invention to list, but all of these fall within the scope of the present invention. Further, where appropriate, singular words should be construed as plural and vice versa, and alternative embodiments do not necessarily mean that the two are mutually exclusive.

[0024] It should be further understood that the present invention is not limited to the specific methods, compounds, materials, manufacturing techniques, uses, and applications described herein, as these may vary. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention. It must be noted that, as used herein and in the appended claims, the singular forms "a", "an", and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, a reference to "a means" is a reference to one or more means and may include subordinate means. All conjunctions used should be understood in the broadest possible sense. Thus, unless the context clearly requires otherwise, the word "or" should be understood to have the definition of "logical or", rather than the definition of "exclusive or" in logic. The structures described herein should be understood to also refer to functional equivalents of such structures.

[0025] For the terms "comprising", "consisting of", and "consisting essentially of", when one of these three terms is used herein, the presently disclosed and claimed subject matter may include the use of either of the other two terms. Thus, in some embodiments not explicitly recited, any case of "comprising" may be replaced with "consisting of", or alternatively with "consisting essentially of".

[0026] The teak slats of the present invention vary in size. It is suitable for outdoor and indoor use, such as decking on luxury ships (e.g., yachts) or manufacturing furniture, and other applications can be interior paneling.

[0027] A method of manufacturing teak slats (60) according to an embodiment of the present invention is described in more detail below. The method includes the following steps:

[0028] a. Debarking the teak log (10) to form a plurality of primary veneers (20);

[0029] b. Obtaining a plurality of defect - free main veneers (20) by repairing the defective areas (22) on the main veneer (20) with a corresponding piece of high - quality secondary veneer;

[0030] c. Combining each main veneer (20) longitudinally and / or transversely using scarf joints and bonding two or more main veneers (20) together with an adhesive to form a plurality of combined veneers (30);

[0031] d. Cross - cutting each combined veneer (30) longitudinally to form a plurality of strips (40);

[0032] e. Laminating the strips (40) under high - pressure compression with an adhesive to form a multi - layer block (50);

[0033] f. Cross - cutting the multi - layer block (50) multiple times to form a plurality of teak slats (60) having a desired thickness and width; and

[0034] g. Kiln - drying each teak slat (60) to have a desired moisture content.

[0035] As used herein, the term "veneer" refers to thin or narrow wood sheets produced by rotary cutting, peeling, or slicing.

[0036] As used herein, the term "peeling" means that when the whole log is mounted on a large lathe and rotated against a blade, the blade peels off long sheets of veneer. Also known as rotary cutting, it produces continuous wide sheets of veneer. The peeling method is the most economical cutting method.

[0037] For all non - rotary - cut veneers, the log is sawn into halves, thirds, quarters, or more. In traditional teak slat manufacturing, slicing methods such as plain slice, rift cut, or quartercut are used to manufacture veneers.

[0038] In the present invention, the veneers obtained by the peeling method are different from the veneers obtained by the slicing method. In rotary peeling, the method follows the tree rings, thus forming distinct irregular markings. Rotary - cut veneers are wide, so they are usually cut to size and defects (if any) are removed. Due to its yield, this is a very cost - effective cutting method. The slicing method is suitable for producing decorative wood veneers and slices. The most common methods are quartercut and crown cut. To produce quarter - cut veneers, the log must be cut into quarters before slicing. The quarter - log is placed on a frame so that the cutting tool meets the tree rings at a right angle. The result is that the veneer has stripes, which may be straight or not depending on the tree species. This slicing technique requires large - diameter trees and the yield is usually lower than the peeling method, which means that quarter - cut veneers may be more expensive.

[0039] Crown cut (also known as plain cut or tangential cut) involves moving the log above the halfway point towards the knife in an up-and-down motion. The slices (called flitches) are stored in sequence as they are cut. This practice is important for the aesthetic of veneer matching projects. Crown cut is a widely used slicing method in veneer manufacturing and typically results in straight grain with interspersed cathedral patterns (also known as crowns).

[0040] Other methods of producing veneer include half-round slicing and quarter slicing, where the log is sliced at a small angle.

[0041] The peeling method of the present invention can be an automated, semi-automated or manual peeling method.

[0042] Depending on the size of the teak log, the size of each primary veneer (20) can be the same or different. For example, the primary veneer can have a thickness (T) between 0.5 mm and 2.0 mm, a width (W) between 1.2 m and 1.5 m, and a length (L) between 1.2 m and 1.5 m.

[0043] Figure 3A 、 3B Figures 3A, 3B and 3C show a teak log (10) peeled into primary veneers (20), the primary veneers (20) having defects (12), and the primary veneers (20) being patched with corresponding numbers of high-quality secondary veneers (24).

[0044] As used herein, the term "scarf joint" refers to a lap joint formed between two veneers by cutting or grooving the ends and securing the two together with ties, bolts or glue. Scarf joints are used when the length of the material being joined is insufficient. Joints other than scarf joints, such as butt joints and splice joints, can be used.

[0045] Figure 4A 、 4B Figures 4A, 4B and 4C show a top view of the combined veneer (30) and top and perspective views of a strip (40) longitudinally cut from the combined veneer (30), respectively.

[0046] The combined veneer (30) is at least 1.5 times wider and / or longer than the primary veneer (20), such as 1.5 times, 2 times, 2.5 times, 3 times, etc. However, the size of the combined veneer varies according to the required size of the teak slat (60). Each combined veneer (30) can have a thickness between 0.5 mm and 2 mm, a width between 60 mm and 180 mm, and a length between 900 mm and 5000 mm.

[0047] To obtain teak slats (60) with a consistent and uniform straight grain pattern, the method of manufacturing teak slats (60) according to the present invention may further include calibrating each strip (40) before the lamination step to obtain strips with the same thickness and uniformity. The strips (40) may have a thickness between 0.5 mm and 2.0 mm, a width between 75 mm and 155 mm, and a length between 900 mm and 5000 mm.

[0048] As used herein, the term "laminating" refers to joining several layers of material (such as wood layers) together by an adhesive or other means.

[0049] Figure 5A 、 5B Figures 5A, 5B, and 5C respectively show a perspective view of a multi-layer block (50) made of laminated strips (40), a front view of the multi-layer block (50) showing one strip layer substantially parallel to another strip layer, and a perspective view of the multi-layer block (50) with a longitudinal cut mark (A-A).

[0050] According to Figure 5C , the multi-layer block (50) is longitudinally cut along the direction of the dotted line A-A perpendicular to the plane of the strip (40) using a saw or similar tool to form teak slats. For example, the teak slats are 30 mm thick, 150 mm wide, and 4000 mm long, with a straight grain.

[0051] As used herein, the term "ripping" is used to describe longitudinally cutting veneer combinations or multi-layer blocks. Ripping can be done using a table saw, a sawing machine, a circular saw, a frame saw, a band saw, or even a hand saw.

[0052] When laminating the strips (40), the adhesive used is selected from the group consisting of polyvinyl acetate (PVA), polyurethane, cyanoacrylate (CA), ethylene-vinyl acetate (EVA), urea-formaldehyde, hide glue, epoxy resin, melamine-based glue, and combinations thereof. The adhesive used can be commercially available or newly prepared according to methods well-known to those skilled in the art. For example, MF-3L / M-610LY from Hexion (Thailand) Co., Ltd. can be used in the lamination step.

[0053] After bonding several layers of strips together by applying an adhesive as discussed above, the resulting wood laminate is introduced into a high-pressure compression under a pressure of between 10 kg / cm 2 to 20 kg / cm 2 for 2 to 5 hours to form the multi-layer block (50). The adhesive used in the lamination step can also be a dyed adhesive.

[0054] The multi-layer block (50) can have a thickness (D) between 30 mm and 300 mm, a width between 80 mm and 120 mm, and a length between 900 mm and 5000 mm. Then, the multi-layer block (50) is longitudinally cut through the body of the multi-layer block (50) to form a plurality of teak slats (60) having a consistent and uniform straight grain pattern. The teak slats can have a thickness between 3 mm and 120 mm, a width between 30 mm and 300 mm, and a length between 900 mm and 5000 mm.

[0055] As used herein, the term "kiln drying" is used to describe the standard process of effectively bringing the moisture level in wood to the "feasible" range. The kiln drying process involves drying the wood in a chamber where air circulation, relative humidity, and temperature can be controlled so that the moisture content of the wood can be reduced to the target point without any drying defects. The kilns used in the present invention can be conventional kilns and dehumidifying kilns. Vacuum kilns and solar kilns can also be used.

[0056] After the kiln drying step, the teak slats have a moisture content between 8% and 20%.

[0057] The method for manufacturing teak slats of the present invention can further include conditioning each strip before the lamination step to obtain a strip with a desired moisture content.

[0058] As used herein, the term "conditioning" is used to describe the process of relieving tension while drying the wood.

[0059] After the conditioning step, the strip has a moisture content between 8% and 20%.

[0060] In an alternative aspect of the present invention, the method for manufacturing teak slats as discussed above can further include sun-drying the teak slats for 24 to 48 hours to mature the color of the teak slats.

[0061] There are various ways to perform surface treatment on teak slats, and the actual way depends on the combination of desired properties. Generally, there are two-step, three-step, and five-step surface treatment processes to ensure the highest quality of teak slats.

[0062] In an alternative aspect of the present invention, the method for manufacturing teak slats as discussed above can further include a finishing step to provide the teak slats with scratch resistance, chemical resistance, moisture resistance, transparency, appearance, gloss, and repairability.

[0063] There are already several different ways to surface-treat teak decks. Starting with natural coatings such as beeswax or linseed oil, the technology in the teak slat industry has evolved to include several different catalyst, water-based, and urethane coating options. Catalytic coatings mix resin with a catalyst to produce a reaction, and this includes catalytic lacquers, conversion varnishes, urethanes, polyesters, and UV curing processes. Water-based coatings and urethane or urethane / acrylic mixtures can be solvent-based or water-based.

[0064] Stains / toners contain translucent colors that block or reduce color change. Wash coats contain a sealer for the base color of the stain while still allowing the wiping glaze to penetrate the pores without changing the background color. Wiping glaze is a colored oil applied to teak slats that fills the pores to provide a subtle base color that highlights the texture. Sealers are a protective layer of a clear coating that locks in the color and provides a smooth surface for the clear coat. Topcoats are a clear coating that provides protection and a finished appearance.

[0065] The surface treatment materials used in the surface treatment steps according to the present invention are selected from the group consisting of: beeswax, linseed oil, catalytic lacquer, conversion varnish, urethane, polyester, urethane / acrylic mixture, stain / toner, wash coat, wiping glaze, sealer, and topcoat. Depending on the requirements, the slats can also be untreated.

[0066] Figure 6 A perspective view of a teak slat obtained by the method of the present invention is shown. The resulting teak slats have a higher density (about 650 kg / m 3 to 900 kg / m 3 ) than natural teak, have a compressive strength close to or higher than that of natural teak, and have a coefficient of thermal expansion (CTE) in the transverse direction of less than 50×10 -6 / °C. This makes it very resistant to moisture and heat. Therefore, the teak slats of the present invention are suitable for decking as well as for making ornaments and furniture.

[0067] Figure 7 A flowchart of a method for manufacturing teak slats according to a specific embodiment of the present invention is shown. The method includes the following steps:

[0068] a. Debark the teak log (10) to form a plurality of primary veneers (20);

[0069] b. Obtain a plurality of defect-free primary veneers (20) by patching the defective areas (22) on the primary veneers (20) with a corresponding piece of high-quality secondary veneer;

[0070] c. Combine each main veneer (20) longitudinally and / or transversely using a spliced joint, and bond two or more main veneers (20) together with an adhesive to form a plurality of combined veneers (30);

[0071] d. Cut each combined veneer (30) longitudinally to form a plurality of strips (40);

[0072] e. Condition each strip (40) to obtain a strip (40) with a desired moisture content;

[0073] f. Laminate the strips (40) under high pressure with an adhesive to form a multi-layer block (50);

[0074] g. Cut the multi-layer block (50) longitudinally multiple times to form a plurality of teak slats (60) with a desired thickness and width; and

[0075] h. Kiln-dry each teak slat (60) to have a desired moisture content; and

[0076] i. Sun-dry the teak slats (60) and inspect the quality of the teak slats (60).

[0077] The teak slats of the present invention have been tested according to JAS (Japanese Agricultural Standard) 1152 2007: Boiling Water Immersion Delamination Test. This is a standard test for structural glued laminated timber. The test consists of the following: Cut the samples into 75 mm, weigh each sample, immerse each sample in boiling water for 4 hours and then cool it in water at 10 degrees Celsius to 25 degrees Celsius for 1 hour, dry the samples in an oven (with circulating air) at 70 ± 3 degrees Celsius until the weight of the samples is between 100% and 110% of the weight before immersion in boiling water. The test is carried out in 2 cycles. The delamination must not exceed 3 mm in length and 0.05 mm in width. In addition, the delamination rate must be less than 5%. From the test results, no delamination was found in the teak decks of the present invention.

[0078] In addition to the above tests, tests on dimensional stability, equilibrium moisture content (EMC), and density were also carried out on teak slats obtained by traditional methods and the method of the present invention. The results are shown in Tables 1 to 3. The test methods will be described below.

[0079] ● Dimensional stability

[0080] The determination of dimensional changes related to relative humidity variations was carried out in accordance with EN 318. This European standard specifies the method for determining the dimensional changes of wood-based panels caused by variations in the relative humidity of the air. Teak wood slats obtained by traditional methods (control samples) and teak wood slats obtained by the method of the present invention (test samples), which were of the same size and without surface treatment steps, were used to conduct the dimensional change test between 65% and 85% relative humidity. The results of dimensional stability are shown in Table 1.

[0081] Table 1. Dimensional stability of teak wood slats obtained by traditional methods and the method of the present invention

[0082] Sample Thickness variation Length variation Control sample 0.5％ 0.38％ Test sample 0.9％ 0.42％

[0083] The results in Table 1 show that there are no significant changes in thickness and length for the teak wood slats obtained by traditional methods and the present invention.

[0084] ● Equilibrium moisture content (EMC)

[0085] In this test, a static weighing method based on using salt solutions to maintain relative humidity was used. The mass transfer between the sample and the ambient air was saturated by the natural diffusion of water vapor. The atmosphere around the sample had a fixed air moisture content for the temperature applied to the salt solution. The sample was sealed in a small glass container containing 10% sodium chloride as the salt solution. The test was set at 65% relative humidity and 70 °C temperature. Both the control samples and the test samples were subjected to 4 cycles of the test. Each cycle consisted of drying the sample at 70 °C for 3 days, soaking the sample in 10% sodium chloride for 1 day, drying the sample at 70 °C for 2 days, and soaking the sample in 10% sodium chloride for 1 day. The results of the equilibrium moisture content (EMC) are shown in Table 2.

[0086] Table 2. Equilibrium moisture content (EMC) of teak wood slats obtained by traditional methods and the method of the present invention

[0087] Sample Equilibrium moisture content Control sample 7.4 Test sample 7.3

[0088] This test measures the hygroscopicity of the sample, which is the tendency of a solid material to absorb moisture from the surrounding environment. At 65% relative humidity, the teak wood slats obtained by the method of the present invention showed almost the same performance as the teak wood slats obtained by traditional methods.

[0089] ● Density

[0090] The process of measuring the density of the teak wood slats began by embedding a steel ball with a diameter of 11.28 millimeters (about 0.444 inches) halfway into the surface of the teak wood slat. The force required to push the ball into the teak wood slat indicates how the density and strength of the teak wood slat are. A higher density indicates greater strength.

[0091] Table 3. Density of teak slats obtained by traditional method and the method of the present invention

[0092] Sample Density (kg / m3) Control sample 631 Test sample 703

[0093] The results in Table 3 show that the teak slats obtained by the method of the present invention have greater strength than those obtained by the traditional method.

[0094] In summary, compared with other natural wood deck / slat "alternatives", the method of the present invention reduces the manufacturing time. Compared with other previous techniques, the method also preserves the beauty of natural teak. The method of the present invention can produce wider and longer teak slats from shorter teak logs. The teak slats obtained by the method of the present invention also have the same or even higher quality compared with those obtained by the traditional method.

Claims

1. A method for manufacturing a teak plank, comprising the following steps: a. peeling a teak log to form a plurality of main veneers; b. by repairing a defective area on the main veneer with a corresponding piece of high-quality secondary veneer to obtain a defect-free main veneer; c. combining each main veneer longitudinally and / or transversely using scarf joints, and bonding two or more main veneers together by an adhesive to form a plurality of combined veneers; d. Each of the combined veneers is cut longitudinally to form a plurality of strips; e. laminating the strips by the adhesive under high pressure compression to form a multilayer block; f. cutting the multilayer block several times longitudinally to form a plurality of teak strips having a desired thickness and width; and g. Kiln-dry each teak plank to the desired moisture content.

2. The method of manufacturing teak planks according to claim 1, wherein each main veneer has a thickness between 0.5 mm and 2.0 mm, a width between 1,200 mm and 1,500 mm, and a length between 1,200 mm and 1,500 mm.

3. The method of manufacturing teak planks according to claim 1, wherein the built-up veneer is at least 1.5 times wider and / or longer than the main veneer.

4. The method of manufacturing teak wood strips according to any one of claims 1 to 3, further comprising calibrating each strip before the lamination step to obtain strips with the same thickness and uniformity.

5. A method of manufacturing teak wood strips according to any one of claims 1 to 3, further comprising conditioning each strip prior to the lamination step to obtain strips having a desired moisture content.

6. The method of manufacturing teak planks according to claim 5, wherein the moisture content is between 8% and 20%.

7. The method of manufacturing teak planks according to any one of claims 1 to 3, wherein each strip has a thickness between 0.5 mm and 2.0 mm, a width between 75 mm and 155 mm, and a length between 900 mm and 5,000 mm.

8. The method of manufacturing teak planks according to any one of claims 1 to 3, wherein the adhesive is selected from the group consisting of polyvinyl acetate (PVA), polyurethane, cyanoacrylate (CA), ethylene vinyl acetate (EVA), urea formaldehyde, hide glue, epoxy resin, melamine-based glue, and combinations thereof.

9. A method of manufacturing teak planks according to any one of claims 1 to 3, wherein the adhesive is a dye adhesive.

10. The method of manufacturing teak planks according to any one of claims 1 to 3, wherein the multi-layer block has a thickness between 75 mm and 155 mm, a width between 150 mm and 300 mm, and a length between 900 mm and 5,000 mm.

11. The method of manufacturing teak planks according to any one of claims 1 to 3, wherein the teak planks have a thickness between 2 mm and 153 mm, a width between 30 mm and 300 mm, and a length between 900 mm and 5,000 mm.

12. The method of manufacturing teak planks according to any one of claims 1 to 3, wherein after kiln drying, the teak planks have a moisture content between 8% and 20%.

13. The method of manufacturing teak planks according to any one of claims 1 to 3, further comprising sun drying the teak planks to mature the color of the teak planks.

14. The method of manufacturing teak planks according to any one of claims 1 to 3, further comprising a surface treatment step to improve scratch resistance, chemical resistance, moisture resistance, clarity, appearance, gloss and repairability of the teak planks.

15. The method of manufacturing teak planks according to claim 14, wherein the surface treatment material used in the surface treatment step is selected from the group consisting of: beeswax, linseed oil, catalyzed lacquer, conversion varnish, urethane, polyester, urethane / acrylic blend, stain / tint, primer, glaze, sealant and topcoat.

16. A teak plank obtained by the method of any one of claims 1 to 15.

17. The teak plank of claim 16, wherein the teak plank has a thickness of less than 50×10 -6 / degrees Celsius lateral coefficient of thermal expansion (CTE).

18. A teak plank as claimed in claim 16 or 17, wherein the top surface of the teak plank has a straight grain pattern.

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