KR102418832B1 - Wood processing method using multi-step grinding operation - Google Patents

Abstract

One embodiment of the present invention provides a wood processing method comprising: (a) a step of preparing dried wood by cutting thereof into a predetermined shape; (b) a step of firstly grinding the wood surface; (c) a step of removing a weakness point of the wood; (d) a step of curing by applying a resin composition to the wood; (e) a step of secondarily grinding the wood surface; and (f) a step of thirdly grinding the wood surface. Therefore, the present invention is capable of suppressing deformation.

Description

Wood processing method using multi-step grinding operation {WOOD PROCESSING METHOD USING MULTI-STEP GRINDING OPERATION}

The present invention relates to a wood processing method using a multi-step grinding operation, and more particularly, to a wood processing method for remarkably improving durability while maintaining the elegant aesthetics of a log.

Wood has excellent workability, durability, electrical insulation, thermal stability, etc. and is applied as a member of various structures. In addition, unlike petrochemical materials, due to the nature of natural materials, harmful substances are not generated, and its unique aesthetics are loved by various consumers.

In general, wood in the form of a plate is used for various purposes by cutting a log having a cylindrical shape in the longitudinal direction and reprocessing it in the form of a plate. In particular, the preference for products that maximize the natural texture and color of wood in this processing process is increasing.

However, wood, which is a natural product, has a problem of being deformed during long-term use by shrinking and relaxing depending on humidity conditions. In addition, there is a problem in that the mechanical strength of the wood itself is insufficient, so that it is easily damaged when applied to furniture.

The developers of the present invention have developed a wood processing method that improves the strength while maintaining the aesthetics of wood from this point of view, and prevents problems due to deformation.

The present invention has been derived to solve the above problems, and an object of the present invention is to provide a wood processing method that improves strength and suppresses deformation while maintaining the aesthetics of the material itself.

One aspect of the present invention for solving the above problem is (a) preparing by cutting the dried wood into a predetermined shape; (b) first polishing the surface of the wood; (c) removing the weakness of the wood; (d) applying a resin composition to the wood and curing it; (e) secondary grinding of the wood surface; And (f) provides a wood processing method comprising the step of third grinding the surface of the wood.

In one embodiment, the wood is pine, cedar, red oak, white oak, ovangol, red zebra, wenge, apromosia, bubinga, chrysanthemum, kouko, monkey pod, purple wood, American black walnut, English walnut , Claro Walnut, Barston Walnut, Zelkova, Camphor, and may be one selected from gypsum.

In one embodiment, the first polishing is performed with sandpaper of 30-100 microns, the second polishing is performed with sandpaper of 10-30 microns, and the third polishing is performed with sandpaper of 2-10 microns. can

In one embodiment, the resin composition may include a compound including one or more aromatic rings and one or more epoxy groups.

In one embodiment, the resin composition may be composed of 30 to 70 parts by weight of 4,4-1-methylethylidene and 30 to 70 parts by weight of polyamide.

In one embodiment, after step (f), (i) applying and curing the undercoat one or more times; (ii) applying and curing a sanding sealer on the undercoat; (iii) polishing the surface of the sanding sealer; and (iv) applying and curing a topcoat on the polished surface.

In one embodiment, the thickness of the coating layer including the undercoat, the sanding sealer and the top coat may be 15 to 100㎛.

In one embodiment, after the step (f), the step of (g) applying and removing the natural oil may be additionally performed one or more times.

One aspect of the present invention can provide a wood processing method for improving strength and suppressing deformation while maintaining the aesthetics of the material itself.

It should be understood that the effects of the present invention are not limited to the above-described effects, and include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

Hereinafter, the wood processing method of the present invention will be described in more detail. However, the following descriptions are provided to facilitate implementation of the present invention by way of example, and the present invention is not limited by the following descriptions.

Wood processing method

Wood processing method according to an aspect of the present invention comprises the steps of (a) cutting the dried wood into a predetermined shape and preparing; (b) first polishing the surface of the wood; (c) removing the weakness of the wood; (d) applying a resin composition to the wood and curing it; (e) secondary grinding of the wood surface; And (f) it may include the step of tertiary grinding of the surface of the wood.

The wood is pine, cedar, red oak, white oak, ovangol, red zebra, wenge, apromosia, bubinga, chrysanthemum, kouko, monkey pod, purple wood, American black walnut, English walnut, clarow walnut, barston It may be one selected from walnut, zelkova, camphor, and gypsum.

The wood may be dried to have a moisture content of 20 to 40%. If the moisture content of the dried wood is too low, the wood may be damaged during the drying process, and if it is too high, it may rot.

The first polishing may be performed with sandpaper of 30-100 microns, the second polishing may be performed with sandpaper of 10-30 microns, and the third polishing may be performed with sandpaper of 2-10 microns. In this way, if the fine grinding is performed sequentially, the aesthetics of the wood surface may be excellent.

The resin composition may include a compound including at least one aromatic ring and at least one epoxy group. When the compound includes one or more aromatic rings, the hardness of the processed wood may be secured, and deformation due to natural drying of the processed wood may be prevented. In addition, one or more epoxy groups may induce curing of the resin composition. In terms of hardness and curing rate of the final product, it may be advantageous to maintain the number of aromatic rings and epoxy groups in the range of 1-2: 1-3.

The resin composition may be composed of 30 to 70 parts by weight of 4,4-1-methylethylidene and 30 to 70 parts by weight of polyamide. For example, a weight ratio of 30: 70, 35: 65, 40: 60, 45, 55, 50: 50, 55: 45, 60: 40, 65: 35 or 70: 30 may be maintained. If these conditions are satisfied, a sufficient degree of curing may be realized and the appearance characteristics may be excellent.

In the above processing method, if the resin composition is treated after polishing with sandpaper with large particles of 30 to 100 microns, the resin can be more easily cured on a relatively rough surface, and then the surface is polished with sandpaper with small particles. By reducing scratches, smooth surface properties can be realized.

closing stage

After the step (f), (i) applying and curing the undercoat one or more times; (ii) applying and curing a sanding sealer on the undercoat; (iii) polishing the surface of the sanding sealer; and (iv) applying and curing a topcoat on the polished surface.

If the undercoat is divided into two or more treatments, it is possible to prevent deterioration of appearance characteristics due to deterioration of the quality of the painted surface.

If the temperature difference between the wood and the painting is maintained at ±0.5° C. or less in the steps (i) to (iv), it is possible to prevent the formation of air bubbles on the painted surface.

The thickness of the coating layer including the undercoat, the sanding sealer and the top coat may be 15 to 100 μm. When the thickness of the coating layer satisfies the above range, it is possible to prevent deterioration of appearance characteristics due to thickening of the coating layer, and to prevent deformation and splitting due to changes in moisture content of wood. It can also improve mechanical strength and prevent chemical denaturation.

After step (f), (g) applying and then removing the natural oil may be additionally performed one or more times. Such an oil finish can maintain the texture of the wood by absorbing the oil into the wood.

Hereinafter, a specific embodiment to which the wood processing method is applied will be described. However, the invention described herein is not limited by the examples below.

Preparation Examples 1-3 and Comparative Preparation Examples 1-2

4,4-1-methylethylidene (A) and polyamide (B) were mixed to prepare a resin composition.

Experimental Example 1

The resin compositions according to Preparation Examples and Comparative Preparation Examples were applied to a plate-shaped wood specimen and cured. A specimen to which the resin composition was not applied was used as Comparative Preparation Example 3.

division Comparative Preparation Example 1 Preparation Example 1 Preparation 2 Preparation 3 Comparative Preparation Example 2 Comparative Preparation Example 3 A:B 10:90 30:70 50:50 70:30 90:10 - burglar 103 124 163 141 109 100 Appearance characteristics × ○ ◎ ○ × ◎

Comparative Preparation Example 1 and Comparative Preparation Example 2 did not sufficiently cure the resin composition, so the strength improvement effect was insufficient, and due to the phenomenon of only partially curing, aggregation occurred on the surface of the specimen, resulting in poor appearance characteristics. Preparation Example 1, In Preparation Example 3, a part of the hardened surface was opaque, so the texture of the wood was somewhat insufficient, but in Preparation Example 2, the same texture as that of Comparative Preparation Example 3, which was wood, was implemented, and a resin hardened surface was formed in the wood hole to show a unique texture This was excellent.

Example 1

The dried wood was flatly cut into a round plate or a rectangular plate shape depending on the shape of the final product. When cutting, only the bark was removed without cutting the edges. The cut wood surface was first polished with 100 micron sandpaper. Vulnerabilities such as knots, splits, and holes in the wood were removed. Thereafter, the resin composition of Preparation Example 2 was applied and cured to reinforce the removed weak points and the surface of the wood. After the resin composition was completely cured, it was secondarily polished with 15 micron sandpaper. The third was polished with 8 micron sandpaper.

Example 2 and Comparative Example 2

The temperature of the wood on which the polishing treatment of Example 1 was completed was adjusted to 22°C, and a transparent urethane undercoat whose temperature was adjusted to 22°C was first applied. After the undercoat was cured, it was applied a second time and cured. After that, a sanding sealer was applied and cured. After the hardened sanding sealer was polished with 15 micron sandpaper, a transparent urethane topcoat was applied and cured to prepare processed wood.

Experimental Example 2

The surface properties of the processed wood prepared in Example 2 and Comparative Example 2 were measured and shown in Table 2 below. Comparative Example 2-3 was set as the case in which a separate coating film was not formed.

division Example 2-1 Example 2-2 Example 2-3 Example 2-4 Comparative Example 2-1 Comparative Example 2-2 Comparative Example 2-3 Thickness (㎛) 20 40 60 80 10 120 - Appearance characteristics ○ ○ ○ ○ × △ ○ drying characteristics ○ ○ ○ ○ △ × △ external force characteristics ○ ○ ○ ○ △ ○ △ discoloration ○ ○ ○ △ ○ △ ○

(○: Excellent, △: Poor, ×: Poor)-Appearance characteristics: It was checked whether there was an abnormality in the coating film on the surface of the processed wood that had been hardened. Excellent when the wood grain can be checked smoothly, poor when there is a defect in the paint film or impairs the aesthetics of the wood surface color or texture, and poor when the paint film is not properly formed.

-Drying characteristics: It was left for 24 hours at a temperature of 50°C and a relative humidity of 10% to check for abnormalities on the surface of the coating film. Those with no damage to the wood were considered excellent, those with cracks were considered insufficient, and those that were split or twisted were considered defective.

-External force characteristics: A 500 g weight was dropped from a height of 50 cm to check whether the coating film was destroyed. Those with no damage to the surface properties were considered excellent, those with dents were considered insufficient, and those with damaged wood were considered defective.

-Discoloration characteristics: Only half of the wood was irradiated with UV with a wavelength of 320 nm for 72 hours to check the degree of discoloration. Those with no discoloration were considered excellent, those with a difference that could be visually identified when compared with the other half were considered insufficient, and those with poor aesthetics without comparison were considered poor.

Claims (1)

(a) preparing the dried wood by cutting it into a predetermined shape;
(b) first polishing the surface of the wood;
(c) removing the weakness of the wood;
(d) curing the wood by applying a resin composition comprising 30 to 70 parts by weight of 4,4-1-methylethylidene and 30 to 70 parts by weight of polyamide to the wood;
(e) secondary grinding of the wood surface; and
(f) comprising the step of tertiary grinding of the wood surface,
The first polishing is performed with sandpaper of 30-100 microns, the second polishing is performed with sandpaper of 10-30 microns, and the third polishing is performed with sandpaper of 2-10 microns Wood processing, characterized in that Way.