JPS59196203A - Manufacture of aggregate 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 involves laminating and integrating wooden veneers using an adhesive.
It belongs to the field of technology related to the production of so-called laminated veneers, which is then sliced to express wood grain artificially.

[Background Art] The conventional method for manufacturing a laminated veneer was as follows.

First, a material veneer is created from raw wood using rotary lace, etc., and this is bleached and dyed as necessary to create the raw material veneer. Next, several tens to hundreds of raw material veneers are stacked together with an adhesive, sandwiched between molds, and pressed together to form a flitch, and this flitch is sliced to form the desired composite unit. I was getting a board.

A particularly important step in the above manufacturing method is the pressing step, and the quality of the flitch obtained is determined by the quality of this step. Therefore, various improvements have been made to the pressing process. For example, when making a thick flitch, it is not possible to obtain the desired thickness at once, so instead of stacking and pressing all the required number of raw material veneers at once, for example, first stack 50 sheets and press. Then, the mold is opened and the next 50 sheets are stacked and pressed together, and the same operation is repeated several times. This kind of multi-stage molding (hereinafter referred to as frisoting) was performed.

However, if you look in detail, even with this manufacturing method,
There are unresolved issues. For example, during frisoting,
Adhesion failure occurred at the adhesive interface between the books, especially at the edges, resulting in a so-called cracked opening. This is explained using drawings in FIGS. 1 and 2. 1st
In the figure, 1 is the mold board. This usually uses a mold plate 1 having a concave and convex curved surface. 2 is the flitch obtained in the previous stage, and this is called bu-tsuk.

A raw material veneer is stacked on top of the book 2 to form a laminate 3 of raw material veneers, and the mold board 1 is pressed in the direction of arrow a to clamp it. Then, as shown in FIG. 2(b), a crack 4 was generated at the joint surface between the book 2, which had already been pressed and hardened, and the book 3a, which was formed by pressing the newly stacked raw material veneers.

This is because, as shown in Figure 2 (a), stress is applied in the direction of the arrow when it is pressed, and the adhesive at the interface is uncured, causing displacement and deformation (as shown by the dotted line). 1. This was caused by poor adhesion.

[Object of the invention] This invention was made under the above circumstances,
This was done to prevent the gaping phenomenon during frisoting.

[Disclosure of the Invention] The present invention provides a method for producing a laminated veneer, which is characterized in that during frisoting, pressure is applied from the lateral direction as well as from the direction of pressure applied during pressing by a mold plate.

A detailed explanation will be given below based on the drawings shown as examples.

FIG. 3 is a process diagram as an embodiment of the present invention, showing a pressing process. In this process, side presses 5 are provided on both sides of the book 2a as shown in the figure, and the side presses 5 are installed in the lateral direction (
The pressure is applied in the direction indicated by arrow C). The lateral direction in this case corresponds to the normal direction to the pressing direction, and the press is arranged so that it can press the uppermost book 2a from both sides. Moreover, it is preferable to arrange it so as to press the side surface of the upper end of the uppermost book 2a. However, this is not intended to be limiting as long as it can be placed on the side and pressed so that the purpose of the invention can be achieved.

Although the pressure of pressing is not limited, it is 11 of the pressing pressure.
A suitable value is 5 to 1/1O, and it is preferable that the timing of pressurization starts almost at the same time as the clamping.

The present invention is a method for manufacturing laminated veneer, and can be applied to a so-called cold press method in which the pressing process is performed at room temperature, or to a case in which the pressing process is performed using a high-frequency heating method. .

Example 1 [In the case of cold pressing] A dyed Agatis veneer was used as a raw material veneer. The thickness of this was 0.8 to 1.2 Tsuru, and 100 sheets were used as a unit of 1 stage. The molding plate used was a sinusoidal mold with a width of 360 squares and a height difference of 57 cranes. Clamping pressure is 15 kg/ca, side press pressure is 3 kg/cn! As a result of the multi-stage embodiment, the cracks at the ends were 50 fins in the conventional method, but were 15 mm in this example, which significantly reduced the number of cracks in the ends.

Example 2 [In the case of high-frequency heating method] A dyed Agatis veneer was used as a raw material veneer. The thickness of this is 0.8~1. 2+ut, 100 sheets were carried out as a unit of one stage. The width of the mold plate is 360mm. True, height difference 57
I used a sine wave pattern for the fabric. However, the mold plate was also used as an electrode. Multi-stage compaction was performed with a compaction pressure of 15 kg/c+a and a side press pressure of 3 kg/cnl.

As a result of the above, the cracks at the ends were 50 m long in the conventional method, but were 20 m long in this example, which significantly reduced the cracks.

Note that the high frequency application conditions were as follows.

Applied voltage: 2000V High frequency: 5 MHz Pressing temperature: 85°C [Effects of the invention] This invention is characterized in that, in the pressing of a multi-stage flitch, the pressing is performed in a direction transverse to the pressing direction at the time of pressing. Therefore, the effect of reducing lip cracking defects was obtained.

[Brief explanation of the drawing]

Figure 1 is a process diagram for explaining the conventional pressing process, Figure 2
The figure is a schematic view of the pressing process and flitch for explaining the drawbacks of the conventional method, and FIG. 3 is a diagram of the pressing process for explaining the present invention in detail. 1 is a mold board 2 is a book 3 is a laminate of raw material veneers 4 is a crack 5 is a side press patent applicant Matsushita Electric Works Co., Ltd.

Claims (1)

[Claims] (1) A method for manufacturing laminated veneers in which raw veneers are laminated with an adhesive interposed, and then pressed between mold plates with uneven curved surfaces, and the flitch is created by multi-stage pressing. A method for manufacturing a laminated veneer, which is characterized in that the multi-stage pressing process involves pressing from a side direction with respect to the pressing direction during pressing.