JP2020001372A - Woody member and manufacturing method therefor - Google Patents

Abstract

To provide a woody member capable of making concentration difference in an early wood and a late wood small, and excellent in appearance, and a manufacturing method therefor.SOLUTION: A wood member has a wood 2 having a plurality of grooves 6 having recess toward inside and arranged with a gap each other in a surface direction in one direction 3, and a wood protective layer 20 coated on one surface 3 of the wood 2 containing the grooves 6. A lower limit of depth D1 of the grooves 6 is 20 μm or more. An upper limit of the depth D2 of the grooves 6 is 900 μm or less. The number of the grooves 6 per unit area is 500 /cmto 8000 /cm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wooden member and a method for manufacturing the same.

  2. Description of the Related Art Conventionally, there has been known an insizing process in which a plurality of holes are perforated in the surface of wood before the resin is applied in order to increase the permeability of the resin into the wood.

  For example, it has been proposed to pierce (drill) the surface of wood to form a hole having a depth of about 3.5 mm on average, and then apply a resin to the surface of the wood including the hole ( For example, see Non-Patent Document 1.)

  The resin is usually toned according to the use and purpose.

Journal of the Japan Wood Science Society Vol. No. 1, pp. 28-35 (2018)

  However, wood includes early wood (spring wood), which is a coarse wood part, and late wood (autumn wood), which is a dense wood part. Since the material of the early wood is coarser than the late wood, the resin easily penetrates, so that the early wood becomes darker in color than the late wood. For this reason, on the surface of the wood after application, the early wood becomes thicker and the late wood becomes thinner. In other words, color shading is produced on the surface of the wood.

  It is required to reduce the difference in shading to obtain an excellent appearance.

  However, the method described in Non-Patent Document 1 has a disadvantage that the above-mentioned shading becomes excessively large, and therefore, an excellent appearance cannot be secured.

  The present invention provides a wooden member which can reduce the difference in shading between early wood and late wood, and which is excellent in appearance, and a method for producing the same.

The present invention (1) provides a wood having a plurality of grooves on its surface which are recessed inward and are arranged at intervals in a plane direction and a wood protective layer applied to the surface of the wood including the grooves. The lower limit of the depth of the groove is 20 μm or more, the upper limit of the depth of the groove is 900 μm or less, and the number of the grooves in a unit area is 500 / cm ² or more and 8000 / cm ² or less, including wood members.

The present invention (2) includes the wood member according to (1), wherein the mass of the wood protective layer per unit area is 35 g / m ² or more and 300 g / m ² or less.

  The present invention (3) includes the woody member according to (1) or (2), further including a surface coating layer applied to the surface of the wood including the groove and / or the surface of the wood protection layer.

The present invention (4) is a first step of irradiating the surface of the wood with an ultraviolet laser to form a plurality of grooves so that the grooves are depressed inward and are spaced apart from each other in the surface direction. A second step of forming a wood protective layer on the surface of the wood including the groove by applying a paint to the surface of the wood including the groove, wherein the lower limit of the depth of the groove is 20 μm And the upper limit of the depth of the groove is not more than 900 μm, and the number of the grooves in a unit area is not less than 500 / cm ^{2 and not} more than 8000 / cm ² , including a method for manufacturing a wooden member. .

  The present invention (5) further includes a third step of applying the treatment paint to the surface of the wood including the grooves and / or the surface of the wood protective layer, wherein the method for producing a woody member according to (4) is further provided. Including.

  The present invention (6) includes the method for producing a wood member according to (4) or (5), wherein in the second step, the wood coating is applied a plurality of times.

  In the wood member of the present invention and the method of manufacturing the same, since the upper limit of the depth of the groove is as shallow as 900 μm or less, excessive penetration of the wood coating applied to the groove can be suppressed. Therefore, the difference in shading of the wood member can be reduced.

In addition, since the number of grooves per unit area is 8000 / cm ² or less, excessive penetration of the wood coating applied to the grooves can be effectively suppressed. For this reason, the difference in density between the wooden members can be further reduced.

  As a result, the wooden member is excellent in appearance.

  In particular, according to the method for manufacturing a wooden member of the present invention, since the surface of the wood is irradiated with the ultraviolet laser, it is possible to suppress the occurrence of scorching on the surface of the wood. Therefore, the appearance is more excellent.

In addition, since the lower limit of the depth of the groove is 20 μm or more and the number of grooves in a unit area is 500 or more per cm ² , a sufficient wood protection effect based on the wood protection layer can be obtained.

1A to 1C are process diagrams illustrating an embodiment of a woody member and a method for manufacturing the same according to the present invention. FIG. 1A shows a process of preparing wood, and FIG. 1B shows a groove formed on one surface of the wood. FIG. 1C shows a step of applying a wood coating to one surface to form a wood protective layer.

  One embodiment of a woody member of the present invention and a method for manufacturing the same will be described with reference to FIGS. 1A to 1C.

  As shown in FIG. 1C, the wood member 1 includes a wood 2 and a wood protection layer 20.

  The wood 2 is, for example, a plate material (plate) having one surface 3 and the other surface (not shown in FIG. 1C) facing each other with an interval in the thickness direction. The one surface 3 is an example of the surface of the wood 2.

  The timber 2 includes an early wood (spring wood) 4 and a late wood (autumn wood) 5. The early wood 4 is a wooden part having a coarse material. The late material 5 is a dense wood part, and more specifically, is denser than the early material 4. Further, on one surface 3 of the wood 2, the early wood 4 and the late wood 5 are exposed toward one side in the thickness direction. That is, when one surface 3 of the wood 2 is viewed from one side in the thickness direction, the early wood 4 and the late wood 5 are visually recognized. Although not shown, usually, the early wood 4 and the late wood 5 are alternately arranged on one surface 3 of the wood 2. One early lumber 4 and one late lumber 5 form one annual ring (lumber formed in one year).

  One surface 3 has a flat surface 16 and a groove 6 recessed inward.

  The flat surface 16 is a plane (principal surface) arranged on one side in the thickness direction on the one surface 3. The flat surface 16 is continuous in the surface direction.

  The groove 6 is a concave portion that is recessed from the flat surface 16 of the wood 2 toward the other side in the thickness direction. Specifically, the groove 6 is a round hole cut out from the flat surface 16 into a substantially cylindrical shape. The groove 6 has, for example, a substantially circular shape in plan view.

  Specifically, the groove 6 is defined by (formed from) a bottom surface 9 and an inner side surface 10 extending from the peripheral edge of the bottom surface 9 to one side in the thickness direction.

  The bottom surface 9 has, for example, a substantially circular shape in plan view.

  The inner surface 10 is orthogonal to the one surface 3 of the wood 2, for example. Further, in a cut surface that cuts the groove 6 along the thickness direction, the two inner side surfaces 10 are parallel to each other. One edge in the thickness direction of the inner side surface 10 is continuous with the flat surface 16.

  The groove 6 is, for example, a laser groove (ultraviolet laser groove) formed by irradiating the one surface 3 of the wood 2 with an ultraviolet laser, which will be described in a later manufacturing method.

  The plurality of grooves 6 are arranged at intervals in a direction along the flat surface 16 (a surface direction, a direction orthogonal to the thickness direction). The plurality of grooves 6 include a plurality of first grooves 7 formed in the early material 4 and a plurality of second grooves 8 formed in the late material 5.

  The first groove 7 is a deep groove that is recessed from the flat surface 16 of the early material 4 toward the other side in the thickness direction. The depth D2 of the first groove 7 is a length in the thickness direction from the flat surface 16 to the bottom surface 9 of the early wood 4, and specific numerical values will be described in detail in the depth of the groove 6 (described later).

  The second groove 8 is a shallow groove that is recessed from the flat surface 16 of the late material 5 toward the other side in the thickness direction and is shallower than the first groove 7. The depth D1 of the second groove 8 is a distance from the flat surface 16 of the blank 5 to the bottom surface 9, and specific numerical values will be described in detail in the depth of the groove 6 (described later).

  The plurality of grooves 6 include grooves having various depths. Therefore, the depth of the groove 6 is represented (shown) in a range. Of the plurality of grooves 6, the depth of the shallowest groove is the lower limit D1 of the depth of the groove 6 (described later), and the depth of the deepest groove is the upper limit D2 of the depth of the groove 6 (described later). Become.

  The lower limit D1 of the depth of the groove 6 is not less than 20 μm, and the upper limit D2 of the depth of the groove 6 is not more than 900 μm.

  Specifically, the plurality of grooves 6 include a shallow second groove 8 and a deep first groove 7, and the plurality of second grooves 8 also include grooves having various depths. The first groove 7 also includes grooves having various depths. The depth of the deepest groove of the first grooves 7 corresponds to the upper limit D2 of the depth of the groove 6, and the depth of the shallowest groove of the second groove 8 is the depth of the groove 6. This corresponds to the lower limit D1.

  If the lower limit D1 of the depth of the groove 6 (the depth of the shallowest groove among the second grooves 8) is less than 20 μm, a sufficient wood protection effect based on the wood protection layer 20 described below cannot be obtained. .

  On the other hand, if the upper limit D2 of the depth of the groove 6 (the depth of the deepest groove among the first grooves 7) exceeds 900 μm, excessive penetration of the wood coating applied to the groove 6 cannot be suppressed. In addition, the difference in density between the wooden members 1 cannot be reduced.

  The lower limit D1 of the depth of the groove 6 is preferably 25 μm or more, more preferably 30 μm or more, and further preferably 50 μm or more. If the lower limit D1 of the depth of the groove 6 is equal to or more than the above, the wood protection effect based on the wood protection layer 20 can be sufficiently exhibited.

  The upper limit D2 of the depth of the groove 6 is preferably 800 μm or less, more preferably 750 μm or less, further preferably 700 μm or less, particularly preferably 600 μm or less, further 500 μm or less, further 450 μm or less. Is preferably 400 μm or less, more preferably 350 μm or less. When the upper limit D2 of the depth of the groove 6 is equal to or less than the above, excessive penetration of the wood coating applied to the groove 6 can be suppressed, and the difference in shading of the wooden member 1 can be reduced.

  The depth (D1, D2) of the groove 6 is obtained by an X-ray microscope. The measuring method will be described in the examples below.

Further, the number of grooves 6 in a unit area is 500 / cm ² or more, or preferably 1000 / cm ² or more, also, 8000 / cm ² or less, or preferably 5000 / cm ² or less .

  If the number of grooves 6 per unit area is less than the above lower limit, the wood protection effect based on the wood protection layer 20 cannot be sufficiently exhibited.

  On the other hand, if the number of grooves 6 per unit area exceeds the above-mentioned upper limit, excessive penetration of the wood coating applied to the grooves 6 cannot be effectively suppressed.

  The number of grooves 6 per unit area is measured (actually measured) by microscopic observation. In addition, it can be set in advance under the conditions of the first step described later.

  The pattern of the plurality of grooves 6 is not particularly limited, and includes, for example, a pattern arranged in the vertical and horizontal directions and a pattern arranged in a staggered pattern in a plan view.

  The average of the maximum length L1 in the surface direction of the groove 6 (the inner diameter if the groove 6 is substantially circular in plan view) is, for example, 20 μm or more, and for example, 100 μm or less, preferably 50 μm or less. It is.

  The length (shortest distance) L2 between adjacent grooves 6 is, for example, 50 μm or more, preferably 100 μm or more, and is, for example, 500 μm or less, preferably 250 μm or less.

  The tree constituting the wood 2 is not particularly limited, and various tree species such as beech, oak, cedar, merkaba, beach, oak, teak, hard maple, cherry, walnut, white ash, mahogany, pine, hiba, and hinoki are available. No. Wood 2 may be any of a veneer and a plywood.

  The wood protection layer 20 is a protection layer that protects one surface 3 of the wood 2 including the plurality of grooves 6 from an external object (for example, dirt or water) or a stimulus (for example, ultraviolet light).

  The wood protection layer 20 is an application layer formed by applying a wood coating to one surface 3 of the wood 2 including the plurality of grooves 6.

  Further, the wood protective layer 20 is formed by penetrating the wood coating material from one surface 3 into the wood 2. The wood protection layer 20 into which the wood coating has penetrated by the application of the wood coating to the first groove 7 is protected by the wood protection layer 20 into which the wood coating has penetrated by applying the wood coating to the second groove 8. It is thicker than the layer 20.

  Further, the wood protection layer 20 may be laminated on one surface 3 (including the bottom surface 9 and the inner side surface 10).

The mass of the wood protective layer 20 per unit area is, for example, 35 g / m ² or more, preferably 40 g / m ² or more, more preferably 75 g / m ² or more, and for example, 300 g / m ² or less. Preferably, it is 250 g / m ² or less, more preferably, 200 g / m ² or less, further preferably, 185 g / m ² or less, particularly preferably, 175 g / m ² or less, most preferably, 150 g / m ² or less. .

  When the mass of the wood protective layer 20 per unit area is equal to or greater than the above lower limit, the wood protective effect based on the wood protective layer 20 can be sufficiently exhibited.

  On the other hand, if the mass of the wood protective layer 20 per unit area is equal to or less than the upper limit, the difference in shading can be reduced.

  Next, a method of manufacturing the wooden member 1 will be described.

  As shown in FIG. 1A, first, for example, a wood 2 having a flat one surface 3 is prepared. One surface 3 of the wood 2 has only a flat surface 16. At this time, the groove 6 has not yet been formed in the wood 2 (that is, a board (plate) in which the groove 6 has not been formed is prepared as the wood 2). The one side 3 can be processed (surface cutting processing) with a planing machine (planer) or the like to increase the smoothness of the one side 3.

  Next, as shown in FIG. 1B, an ultraviolet laser is irradiated on one surface 3 of the wood 2 (first step).

  First, for example, although not shown, a groove forming device including a moving device and an irradiation device is prepared.

  The moving device is equipped with a control device (such as a galvano scanner). The moving device includes a driving source, and can move the irradiation device in the surface direction of the wood 2 based on the driving force of the driving source.

  The irradiation device includes an irradiable ultraviolet laser irradiation unit. Specifically, the ultraviolet laser irradiation unit can irradiate the ultraviolet laser with a pulse based on an excitation method such as laser diode (LD) excitation, for example. The pulse is obtained at a high output, for example, by a Q-switch.

  The above-described groove forming device is not particularly limited, and is appropriately selected from, for example, the devices described in Non-Patent Document 1 described above.

  The wood 2 is set in the above-described groove making device such that one surface 3 of the wood 2 faces the irradiation device.

  Next, under the control of the control device, based on the driving of the moving device, the one side 3 of the wood 2 is irradiated with the ultraviolet laser while scanning the irradiation device in the surface direction.

The irradiation condition is such that the lower limit D1 of the groove 6 is at least 20 μm or more, the upper limit D2 of the depth of the groove 6 is at least 900 μm or less, and the number of the grooves 6 per unit area is 500 / cm ² or more and 8000 / cm ^2. It is set to be as follows.

  Specifically, the wavelength of the ultraviolet laser is, for example, 200 nm or more, preferably 300 nm or more, and is, for example, 400 nm or less, preferably 380 nm or less.

  The pulse energy at one time is, for example, 10 μJ or more, preferably 100 μJ or more, and is, for example, 500 μJ or less.

  The pulse width is, for example, 1 ns or more, preferably 5 ns or more, and is, for example, 50 ns or less, preferably 25 ns or less.

  Further, in order to form one groove 6, the ultraviolet laser can be irradiated once or the same groove 6 can be irradiated plural times (multiple pulses). The number of irradiations is appropriately set depending on the degree of denseness of the material of the tree species.

  Thereby, a plurality of grooves 6 are formed on one surface 3 of the wood 2.

  Then, as shown in FIG. 1C, a wood coating is applied to one surface 3 of the wood 2 including the groove 6 (second step).

  The wood coating is not particularly limited, and includes, for example, an active ingredient (preservative, fungicide, etc.), a toning component, a film-forming component (including a water-repellent component), a solvent, and the like. Such wood coatings include known wood coatings. As the wood coating, commercially available products can be used. For example, Xyladecor Interior Fine (manufactured by Osaka Gas Chemical Co., Ltd.), Konzoran series (manufactured by Osaka Gas Chemical Co., Ltd.), water-based VATON series (manufactured by Otani Paint Co., Ltd.), etc. For example, oil-based wood coatings such as oil-based Xyladecor series (manufactured by Osaka Gas Chemical Co., Ltd.) and VATON series (manufactured by Otani Paint Co., Ltd.) are used. Further, as a wood coating, a wood protection coating that conforms to the Architectural Institute of Japan material standard “JASS 18M-307” is also suitable.

  The application method is not particularly limited, and examples thereof include brush coating, spatula coating, and spray coating. Preferably, brush coating is used.

The number of times of application is not particularly limited. One time or multiple times may be used. From the viewpoint of setting the mass of the wood protective layer 20 in the above range (specifically, a high value of 35 g / m ² or more), a plurality of times is preferable. If the number of times of application is plural, the wood protective layer 20 having a large mass can be formed.

  The applied wood coating material permeates into the wood 2 from one side 3.

  Then, if necessary, cure at room temperature (20 ° C.). Thereby, the solvent of the wood coating is removed.

  Thereby, the wood protection layer 20 is formed on the one surface 3 including the groove 6.

  In the woody member 1 of this embodiment and the method of manufacturing the same, the upper limit D2 of the depth of the groove 6 is as shallow as 900 μm or less, so that excessive penetration of the wood coating applied to the groove 6 can be suppressed. Therefore, the difference in shading of the wooden member 1 can be reduced.

Further, since the number of grooves 6 per unit area is 8000 / cm ² or less, excessive penetration of the wood coating applied to grooves 6 can be effectively suppressed. Therefore, the difference in shading in the wooden member 1 can be further reduced.

  As a result, the wooden member 1 is excellent in appearance.

  In particular, according to the method of manufacturing the wooden member 1, since the ultraviolet laser is applied to the one surface 3 of the wood 2, it is possible to prevent the one surface 3 of the wood 2 from being scorched. Therefore, the appearance is more excellent.

In addition, since the lower limit D1 of the depth of the groove 6 is 20 μm or more and the number of the grooves 6 per unit area is 500 or more / cm ² , the wood protection effect based on the wood protection layer 20 is sufficiently exhibited. Can be.

Furthermore, if the mass of the wood protective layer 20 per unit area is 35 g / m ² or more, the wood protective effect based on the wood protective layer 20 can be sufficiently exhibited. On the other hand, if the mass of the wood protective layer 20 per unit area is 300 g / m ² or less, the difference in shading can be reduced.

  In addition, if the wood coating is applied a plurality of times in the second step, the mass of the wood protective layer 20 per unit area can be easily set in the above range.

  A wood member 1 including a wood 2 having no groove 6 (for example, the wood 2 shown in FIG. 1A) and a wood protection layer 20 formed by applying a wood coating to the wood 2, Compared with the wood 2 having the groove 6 and the wood protection layer 20 formed by applying the wood coating to the wood 2 and comparing the wood member 1 shown in FIG. 1C, its weather resistance (for example, repellency) Needless to say, the latter is much better in terms of weather resistance (evaluated in water).

Modifications In the following modifications, detailed descriptions of components and steps similar to those of the above-described embodiment will be omitted. Further, each modified example has the same operation and effects as those of the embodiment except for special mention.

  As shown by the imaginary line in FIG. 1C, the wooden member 1 can further include an undercoat layer 15 as an example of a surface coating layer.

  The undercoat layer 15 is formed, for example, after the grooves 6 are formed and before the wood coating is applied to the one surface 3 of the wood 2, the undercoat as an example of the processing paint is applied to the wood 2. It is formed by applying to one surface 3 (third step). The undercoat paint (clear paint) contains, for example, an acrylic resin, an alkyd resin, a polyester resin, a polyurethane resin, an epoxy resin, a silicone resin, a fluororesin, and other resins, and an organic solvent.

  If the wooden member 1 further includes the undercoat layer 15, the difference in shade can be further reduced.

  Further, as shown by the imaginary line in FIG. 1C, the wooden member 1 can further include an overcoat layer 17 as an example of a surface coating layer. The topcoat layer 17 is formed by applying a topcoat paint as an example of a treatment paint on the surface of the wood protective layer 20. The overcoat paint contains, for example, the above-mentioned resin and organic solvent.

  If the wooden member 1 further includes the overcoat layer 17, the difference in shading can be further reduced.

  Alternatively, the wooden member 1 can include both the undercoat layer 15 and the overcoat layer 17.

  In one embodiment, the groove 6 is formed only on the one surface 3, but may be formed on both surfaces of the one surface 3 and the other surface (not shown).

  In one embodiment, the wood 2 is described as a plate material, but is not limited thereto, and may be, for example, a log.

  In one embodiment, the shape of the groove 6 in plan view is not particularly limited, and may be, for example, a substantially polygonal shape (for example, substantially rectangular shape) in plan view.

Further, in one embodiment, the grooves 6 in the wooden member 1, a UV laser is described as an ultraviolet laser grooves formed by irradiating one surface 3 of the timber 2, the short pulse CO ₂ laser wood 2 A short-pulse CO ₂ laser groove formed by irradiating one surface 3 may be used.

  Further, the groove 6 may be, for example, a perforated groove formed by a physical cutting method (for example, needle processing).

  Specific numerical values such as the number of blending parts (content ratio), physical property values, parameters, and the like used in the following description are the corresponding number of blending parts (content ratio) described in the above “Embodiment for carrying out the invention”. ), Physical property values, parameters, etc., may be replaced by the upper limit (the value defined as “less than” or “less than”) or the lower limit (the value defined as “above” or “exceeding”) it can.

Example 1
As shown in FIG. 1A, first, an air-dried cedar core and straight-grained wood whose one surface 3 was flattened with a planer was prepared as wood 2.

  Next, an LD-pumped Q-switched solid-state laser (TALON-355-15SH, manufactured by Spectra-Physics) equipped with a galvano scanner (YD-200-OP, manufactured by YE Data) was used under the following conditions. Then, the one side 3 of the wood 2 was irradiated with an ultraviolet laser.

Wavelength 355nm
Pulse width 12 ns
Pulse energy 240μJ
At this time, a dispersion irradiation method in which the laser is continuously oscillated while the galvano scanner is continuously scanned without stopping for each groove 6 is adopted. In the above apparatus, the scanning speed and the like were set so that the number of grooves 6 to be formed was as shown in Table 1.

  Thereby, as shown in FIG. 1B, a plurality of grooves 6 were formed on one surface 3 of the wood 2.

  Thereafter, a brown wood coating (commercially available, solid content concentration: 27.5% by mass) conforming to the Architectural Institute of Japan material standard "JASS 18M-307" is applied five times to one side 3 of the wood 2 with a brush. (Painted).

  Thus, as shown in FIG. 1C, the wood protective layer 20 was formed. Thereafter, the wood 2 was cured at normal temperature (20 ° C.) for one week.

Examples 2 to 15 and Comparative Example 1
Except that the manufacturing conditions (depth of groove 6, number of grooves 6 per unit area, number of times of application of wood coating, mass of wood protective layer 20 per unit area, etc.) were changed according to Tables 1 and 2, The same procedure was used as in 1.

Example 16
After forming the plurality of grooves 6 on one surface 3 of the wood 2 and before applying the wood coating to the wood 2, a colorless and transparent undercoat conforming to the Architectural Institute of Japan material standard “JASS 18M-307” A paint (commercial product, solid content concentration: 18% by mass) is applied once to the one surface 3 of the wood 2 with a brush (brush coating) to form an undercoat layer 15 as shown by a virtual line in FIG. 1C. Except having performed, it processed similarly to Example 1.

<Evaluation>
The following items were evaluated. The results are shown in Tables 1 to 3.

Depth The lower limit D1 and the upper limit D2 of the depth of the groove 6 were determined by an X-ray microscope and an image analyzer. Details of the measurement and analysis are as follows.
X-ray microscope nano3DX (Rigaku)
Tube voltage 40kV
Tube current 30mA
X-ray target Copper image analyzer Image processing software Image J

Weight of Wood Protective Layer From the weight difference before and immediately after application, the weight of the wood coating material per unit area (including data on solid content and solvent) was determined, and the solid content concentration (27.5% by mass) ) To determine the mass of the wood protective layer 20 per unit area.

Mass of undercoat layer From the mass difference between before and immediately after application, determine the mass of the undercoat paint per unit area (including data on solid content and solvent) and then divide by the solid content concentration (18 mass%). The mass of the undercoat layer 15 per unit area was determined.

Difference in shading About the woody member 1 of each Example and Comparative Example, according to JIS K 5600-7-7, using a xenon weather meter (manufactured by Atlas Co., Ltd.), a black panel temperature of 63 ° C., a 120 minute cycle (irradiation for 102 minutes) , Followed by irradiation for 18 minutes and spraying) for up to 1000 hours.

  Thereafter, the wooden member 1 was cured under an atmosphere of 20 ° C. and 65% RH.

After that, the difference in shading between the early wood 4 and the late wood 5 in the wooden member 1 was visually evaluated according to the following criteria.
A: The difference in shading between late wood 4 and early wood 5 was extremely remarkably minute.
：: The difference in shading between late wood 4 and early wood 5 was extremely small.
Δ: Difference in shading between late wood 4 and early wood 5 was minute.
X: The difference in shading between the late wood 4 and the early wood 5 was excessive.

Evaluation of Water Repellency About 1 g of distilled water was dropped on one surface 3 of the wood 2, left for 1 minute, and then the water drops were wiped off.

Water repellency (%) = (1−permeation amount / drop amount) × 100
When the percentage of water repellency is high, more specifically, when the percentage of water repellency is close to 100%, the effect of protecting the wood on the one surface 3 of the wood 2 of the wood protection layer 20 is sufficiently exhibited. Show.

Reference Signs List 1 wood member 2 wood 3 one surface 6 groove 15 undercoat layer (an example of surface coating layer)
17 Topcoat layer (example of surface coating layer)
20 Wood protection layer D1 Lower limit of groove depth D2 Upper limit of groove depth

Claims (6)

Wood having a groove that is recessed toward the inside and has a plurality of grooves arranged on the surface at intervals in the plane direction,
A wood protective layer applied to the surface of the wood including the groove,
The lower limit of the depth of the groove is 20 μm or more, the upper limit of the depth of the groove is 900 μm or less,
A wood member, wherein the number of the grooves in a unit area is not less than 500 / cm ^{2 and not} more than 8000 / cm ² . Mass of the wood protection layer in the unit area, 35 g / ^{m 2} or more, the wood member as claimed in claim 1, characterized in that 300 g / ^{m 2} or less.   The wood member according to claim 1 or 2, further comprising a surface coating layer applied to a surface of the wood including the groove and / or a surface of the wood protection layer. A first step of irradiating the surface of the wood with an ultraviolet laser to form a plurality of grooves so that the grooves are depressed inward and are spaced apart from each other in a plane direction;
A second step of forming a wood protective layer on the surface of the wood including the groove by applying a wood coating to the surface of the wood including the groove,
The lower limit of the depth of the groove is 20 μm or more, the upper limit of the depth of the groove is 900 μm or less,
A method for manufacturing a wooden member, wherein the number of the grooves in a unit area is not less than 500 / cm ^{2 and not} more than 8000 / cm ² .   The method for producing a wood member according to claim 4, further comprising a third step of applying a treatment paint to a surface of the wood including the groove and / or a surface of a wood protection layer.   The method according to claim 4, wherein in the second step, the wood coating is applied a plurality of times.

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