JPS6031902A - Manufacture of aggregate decorative veneer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field] This invention is a so-called veneer assembly technique in which wooden veneers are integrated using adhesive and then sliced to express the wood grain artificially. Belongs to a field.

[Background technology] Conventionally, in the manufacturing method of laminated veneers, adhesive was interposed between the raw veneers and laminated and pressed together, but as the manufacturing technology of laminated veneers became generalized and put into practical use. , efforts have been made to reduce the number of steps, improve workability, and reduce costs. However, there have been no examples with sufficient results yet.

(1) On the other hand, when the obtained laminated veneer is commercialized as building materials, fixtures, or furniture, it is bonded to a base material such as plywood or particle board, and is commercialized in a composite state. In this case, in order to attach the material to the base material, an adhesive such as a vinyl acetate adhesive is usually applied, and the adhesive is bonded by hot pressure molding to form a composite. Streamlining the pasting operation in this case has also become an important technical issue.

[Object of the Invention] The object of the present invention is to rationalize the pressing process in the manufacturing method of laminated veneer and to improve the workability of laminated veneer.

[Disclosure of the Invention] This invention is a process for compressing wood veneers by acetylating the functional groups of cellulose and lignin in the wood veneers used in the manufacturing method of laminated veneers to impart heat-melting properties. It has the following characteristics.

For acetylation, it is usually sufficient to use the same conditions as when acetylating cellulose or the like, but this is not intended to be limiting.

(2) On the other hand, if heat forming is performed by applying high frequency in the pressing process during the production of laminated veneers, the effects of the present invention will be even greater. In other words, the surface of the acetylated wood veneers melts, improving the adhesion between the veneers and significantly reducing the amount of adhesive used. The obtained laminated veneer has excellent workability, and when the laminated veneer is actually attached to a substrate, it becomes more compatible with the substrate and its adhesion is improved.

Furthermore, by further acetylating the surface of the laminated veneer obtained by the above method, it can be attached to a base material without an adhesive or with a reduced amount of adhesive used. . In addition, by applying hot pressure during the pressure bonding process, the surface of the veneer melts, imparting adhesion to the base material, and making it easier to bond without adhesive.

Techniques required to manufacture laminated veneers other than those described above can be achieved by employing known methods.

Example 1 In order to match the (3) color tone of South Sea broad-leaved wood to natural walnut, it was dyed with an acid dye and air-dried. This veneer was permeated in an acetic anhydride-acetic acid-concentrated sulfuric acid reagent at room temperature for 2 hours. After the treatment, the veneer was washed with water, washed with a water-ethanol system, and further conditioned to have a moisture content of 20 to 40%. Adhesive (urethane adhesive) was applied to the humidity-controlled veneer. The amount of adhesive applied was 60 g/rd. As a comparative example, an untreated veneer was coated with 100 g/rd of adhesive and subjected to compression. The pressing conditions were the same for both treated and untreated veneers.

The veneers coated with adhesive were laminated in a mold having an uneven curved surface and pressed together. At the time of pressing, a high frequency oscillator was used to apply high frequency waves between the upper and lower molds to heat the laminate and perform pressing. The high frequency application conditions include a frequency of 5 MHz,
The applied voltage was 3000 V, the application time was 5 minutes, and the number of laminated veneers used in one press-clamping was 100. The obtained laminate was sliced into 0.5 m thick pieces so that the grains were exposed to obtain built-up veneers.

(4) The obtained laminated veneer showed no adhesion defects and was a laminated veneer with high fidelity to natural wood grain. Although similar results were obtained in the comparative example, complete adhesion could not be achieved unless a large amount of adhesive was used.

After air-drying the laminated veneer obtained above, it was again acetylated under the following conditions. That is, infiltration treatment was carried out in an acetic anhydride-acetic acid-concentrated sulfuric acid reagent at room temperature for 2 hours, and after the treatment, washing with water was carried out.
Further, after washing with water and ethanol, air drying was performed to obtain an acetylated laminated veneer.

The above acetylated laminated veneer was subjected to heat and pressure conditions for 1
It was attached to the substrate at 50°C, 20 kg/aJ, and 5 minutes. A 5-fi thick plywood was used as the base material, and the adhesive was not applied to the plywood.

The adhesive strength of the composite of the laminated veneer and the base material obtained under the above conditions was evaluated by measuring the plane tensile strength. In addition, by a conventional method, 100 g/r of vinyl acetate adhesive was applied to the plywood.
The adhesion strength of the composite obtained by coating the composite and molding it under heat and pressure conditions of 110° C. for 2 minutes was also measured (5) and compared with the case described above.

Acetylated laminated veneer 8±2 kg / c4 conventional method
10±2 kg/- As described above, the value was almost the same as that of the conventional method, and the acetylated laminated veneer could be bonded to the base material without using an adhesive.

[Effects of the Invention] The acetylation treatment on the surface of the veneer has the effect that the amount of adhesive used can be reduced in the method for manufacturing laminated veneers.

Patent Applicant Matsushita Electric Works Co., Ltd. Patent Attorney Toshimaru Takemoto (2 people) Manufacturing process 3, relationship with the case of the person making the amendment Patent applicant address 1048 Kadoma, Kadoma City, Osaka Name (5)
83) Matsushita Electric Works Co., Ltd. Representative: Iku Kobayashi 4, Agent address: 1048-5 Oaza Kadoma, Kadoma City, Osaka Prefecture, Date of amendment order: November 29, 1981 7, Details of the amendment as shown in the attached sheet The name of the invention in the title of invention column on page 1 of the book is corrected to "Process for manufacturing laminated decorative veneer."

that's all (1)

Claims (1)

[Claims] (1) A method for manufacturing a laminated veneer, characterized in that the surface of the wood veneer used is acetylated and subjected to compaction.