JPH0327903A - Manufacture of woody decorative veneer - Google Patents

Abstract

PURPOSE:To prevent the generation of heat yellowing and improve the appearance by applying a urethane bonding agent mixed with an oxidation inhibitor to a thinly sliced wood piece, compression molding the same to manufacture a flitch and slicing. CONSTITUTION:A thinly sliced wood piece 1 manufactured by slicing a timber first treated with a chemical and dried, and a urethane bonding agent is applied to the sliced piece 1 and compression molded to manufacture a flitch 3. The flitch is sliced by a slicing blade 4 to form a woody decorative veneer 5. When the urethane bonding receives heat or light, active points are generated and effect chain reaction to generate a peroxide, and the urethane bonding agent is decomposed to generate yellowish color. Chain reaction can be prevented by adding a primary oxidation inhibitor and peroxide is removed by adding a secondary oxidation inhibitor to prevent the urethane bonding agent from decomposing. Heat yellowing can be prevented by said process and the appearance can be improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a decorative wood veneer that is formed by pressing and forming thin pieces of wood into blocks using Pine Goo as an adhesive, and slicing the block-formed flitches. The present invention relates to a manufacturing method.

E-jubei technology] In recent years, as building materials have diversified, there has been a demand for materials with a novel appearance. In particular, there is a need for decorative wood LLT boards that do not impair the warmth and gentleness of wood and have an appearance that can be adapted to modern living spaces. As a wood decorative veneer that satisfies such requirements, the author of this patent previously cited Japanese Patent Application No. 756 (1982-21). For such items, apply adhesive to thin wood pieces and press them into blocks to form flitches, and then slice the flitches to create decorative wood veneers! J! I'm leaving behind.

[Problem to be solved by the invention] The wood decorative veneer manufactured in this way does not impair the beauty of the wood and has an appearance that can be used in modern living spaces, but the adhesive is sensitive to heat and heat. There was a problem that the appearance deteriorated due to thermal yellowing due to the influence of light. Recently, this type of decorative wood veneer has come to be used as flooring material, and at the same time, it has also been used as a flooring material. % or steam to heat the surface side of the floor or the floor itself, and the wood decorative veneer itself has come to be required to have heat resistance (resistance to heat yellowing).

The present invention has been made in view of the above points, and an object of the present invention is to provide a method for manufacturing a decorative wood veneer that can prevent thermal yellowing and improve the appearance.

[Means for Solving the Problem] In order to achieve the above object, the method for producing a decorative wood veneer of the present invention is to apply a urethane adhesive mixed with an antioxidant to a thin piece of wood.
This method is characterized in that the flitch 3 is formed by applying the flitch 3 to the flitch 3 and slicing the flitch 3.

[Function] By using urethane adhesive, it is possible to create a wood decorative veneer with excellent thermal properties that are resistant to thermal deformation and thermal deterioration.Moreover, by mixing an antioxidant into the urethane adhesive, urethane adhesive can be used. Prevents oxidation of adhesive and prevents it from yellowing due to heat and light.

[Example] As shown in FIG. 1, a thin piece of wood 1 obtained by slicing wood is first treated with chemicals, then dried, then a urethane adhesive is applied to the thin piece of wood 1, and then the thin piece of wood 1 is formed using a press device 2. The flitch 3 is pressed and shaped, and the flitch 3 is sliced with a slicing blade 4 to form a wood decorative veneer 5. The thickness of the wood slice 1 is 0.05~
0. 80 questions (preferably 0.10-0.50+*m)
and the area is 6-400mm” (preferably 25mm).
-250mm2), and the aspect ratio (height/width) is 0.4~
7.0 (preferably 0.8 to 3.0). These wood flakes 1 may be rolled up. Also, as long as the above shape accounts for 60% or more, dimensions other than the above may be included. Chemical treatments include dyeing treatments, insect repellent treatments, antiseptic treatments, and flame retardant treatments. The dyeing process is carried out, for example, by dipping the inner basket 8 containing the wood slices 1 into the dyeing liquid 7 in the dyeing tank 6, as shown in FIG. The application of urethane adhesives (excluding urethane adhesives) to wood flakes is done by spraying or kneading. This urethane adhesive contains antioxidants. The pressing of the thin wood piece 1 coated with urethane adhesive is carried out with the press i[2, but with the WI
As shown in Fig. J1, a thin piece of wood 1 is placed in a container n9 and pressed by a press plate 10 to form the mold.

The pressure applied by this press device 2 is sufficient to crush the wood flakes 1 along the press surface, and is 2 Kg.
/ am" - 25 Kg/cm" (preferably 7 Kg/am2 to 14 Kg/cm"). The flitch 3 formed by press molding is sliced with a slicing blade 4 to form a decorative wood veneer 5. This wooden decorative veneer 5 is then laminated onto a substrate such as plywood and used for flooring, etc.

By the way, in the case of the present invention, since the wood thin pieces 1 are bonded using a urethane adhesive, it has excellent thermal properties such as being resistant to thermal deformation and thermal deterioration. However, when it is exposed to heat or light, it suffers from thermal yellowing. It is generally thought that this thermal yellowing is caused by the benzene rings in the urethane adhesive being easily decomposed into active sites (fusicals) generated by heat, and the decomposition products producing a yellow color. To prevent this, antioxidants, which are chemicals that prevent decomposition, are mixed into urethane adhesives. This antioxidant contains a primary antioxidant and a secondary antioxidant. This primary antioxidant is an inhibitor that prevents the chain reaction of active sites generated by heat and light (4'), and the secondary antioxidant removes peroxides that contribute to the active sites rising and causing decomposition. It is an inhibitor that prevents To explain in more detail,
As shown in Figure 2, when urethane adhesive is exposed to heat or light, active points (lanocal) are generated, a chain reaction occurs, peroxide is generated, and the urethane adhesive decomposes, producing a yellow color. However, adding a primary antioxidant can prevent chain reactions, and adding a secondary antioxidant can remove peroxides, suppress decomposition of the urethane adhesive, and prevent yellowing. The present invention will be explained below using specific examples. (Specific example 1 of the present invention) As the wood thin piece 1, a rice fir shaver product with a thickness of 0.2-
Using 0.5m + diameter, SuminoI was used as the dye.
Using 0.1% Milling Brown 3 G (manufactured by Sumitomo Chemical Industries), the wood thin piece 1 was immersed at 95° C. for 1 hour and dyed. This was dried at 1]0°C for 2 hours, and the humidity was adjusted by adding 10% water (dry) by spray. Urethane adhesive GA854. (
(manufactured by Sumitomo Duress), polymer type 7-enol Irganox2 45 (Ciba Iggy 91) was used as the primary antioxidant, and sulfur-based DL was used as the secondary antioxidant.
Using TP (Yoshitomi) (Yoshitomi Pharmaceutical!!), 0.2 parts by weight of primary antioxidant and 0.2 parts by weight of secondary antioxidant were mixed with 100 parts by weight of urethane adhesive.This adhesive The adhesive was applied by spray at a ratio of 300 g to 1 wood thin piece of iooog and kneaded for 10 minutes.The wood thin piece 1 coated with this adhesive was pressed into shape using a formwork.The conditions for this pressing were as follows. The pressure was 15 Kg/am2 for 2 hours.

The flitch 3 obtained by this compression molding was sliced into 0.5 mm thick pieces to obtain a decorative wood veneer 5. (Specific Example 2 of the Present Invention) It is believed that adding an ultraviolet absorber to the antioxidant of Specific Example 1 will further prevent thermal yellowing and improve light resistance at the same time. The same procedure as in Example 1 was carried out using the adhesive as shown below.

(Comparative Example) The same procedure as in Example 1 was carried out without adding an antioxidant to the urethane adhesive.

(Results) The above specific examples 1 and 2 of the present invention and comparative examples were heated to lri.
The results of the tests and light resistance tests are shown in the table below.

The thermal tlt4i test was conducted at a temperature of 80° C. for 2 weeks.

For the light resistance test, carbon arc lamp irradiation was performed for 48 hours.

ΔE is the color difference according to the Hunter color system values L X , aX , and bX As mentioned above, it was found that the antioxidant prevents thermal yellowing of the decorative wood veneer. It has also been found that if an ultraviolet absorber is also added, thermal yellowing can be further prevented and light resistance can be improved.

[Effect of the invention 1 As described above, the present invention uses a urethane adhesive, so it has excellent thermal properties such as being resistant to thermal deformation and thermal deterioration.Moreover, the urethane adhesive is mixed with an antioxidant. Therefore, the antioxidant prevents the urethane adhesive from decomposing and yellowing due to heat, and even when used as a flooring material to heat the entire floor, it also prevents yellowing due to heat. It is possible to improve the appearance.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the manufacturing process of an embodiment of the present invention, f
Figure JS2 is an explanatory diagram illustrating the thermal yellowing process of the same as above, in which 1 is a thin piece of wood, 3 is a flitch, and 5 is a decorative wood veneer. Figure 2

Claims (1)

[Claims] [1] A method for producing a decorative wood veneer, which comprises applying a urethane adhesive mixed with an antioxidant to a thin piece of wood, forming a block by pressure molding to form a flitch, and slicing the flitch.