JPS60115402A - Manufacture of parallel flitch - 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 relates to parallel plywood used as interior building materials.

[Background technology] Parallel plywood (LVL) is made by removing flaws such as knots in natural wood (LVL).
It is widely used as an interior material for houses because it can remove or disperse the effects of air pollution and reduce its effects as much as possible. This parallel plywood is made as follows. In other words, it is obtained by degreasing, warming, and dyeing wood veneers obtained by ro-crislicing, etc. as necessary, making the fiber directions parallel, laminating them with adhesive, and pressing them. .

The parallel plywood obtained in this way has a low veneer density and is laminated with the fiber directions parallel.
There was a problem in that warping and twisting were likely to occur due to shrinkage.

[Purpose of defense].

This invention was made in view of these circumstances,
The purpose is to provide a method for making parallel plywood with less bending and twisting.

[Disclosure of the invention].

This birth is 1. The gist is a method for producing parallel plywood characterized by using wood veneers with increased density through hot pressing, in which parallel plywood is obtained by laminating and pressing wood veneers with adhesive. . This will be explained in detail below.

Figure 1 shows an example of dyeing a wood veneer.

FIG. 2 shows an example of a hot press according to the present invention. FIG. 3 shows an example of a press for forming parallel plywood according to the present invention.

The material is wood veneer obtained by rotary lace etc. or wood veneer obtained by slicing, and these material veneers are degreased and bleached as necessary.
- Prepare. Next, as shown in FIG. 1, for example, while moving the bleached wood veneer 1 in the direction of the arrow B,
A pair of upper and lower roll coaters 2a and 2b rotating in direction B'
The dyes 3a and 3b are applied and dyed. Dyeing is not limited to the double-sided roll coater method as shown in FIG. 1, but can also be done by a spray method, a dipping method, or the like. While moving the dyed veneer 4a thus obtained in the direction of arrow C as shown in FIG.
Pot press roll (thermal pressure roll) 5a that rotates in the force direction
, 5b for hot pressing. The hot press is not limited to a hot press roll as shown in FIG. 2, but may also be a hot press plate.

Such hot pressing allows the dye to penetrate into the interior of the veneer and makes it more dense. Surface pressure during hot pressing is 30 to 60 kg/
The cJ temperature is preferably 200 to 270°C. When hot pressed under these conditions, the veneer undergoes plastic deformation and its density increases, with a specific gravity of 0.38 to 0.42. Or, the volume after compression is 60 to 75%, and when it is made into parallel plywood, warping and twisting are less likely to occur. Ma,
In addition, the high-temperature press also produces a drying effect, so it is possible to control the dyeing property by temperature (low temperature is bad, high temperature is good). As shown in FIG. 3, the hot-pressed dyed veneer 4b is produced by laminating about several tens of veneers with their fiber directions parallel and using an adhesive, as shown in FIG. The parallel plywood 7 is obtained by pressure forming between the two.

The parallel plywood thus obtained is hard and dense, with significantly less warping and twisting.

Parallel plywood using dyed veneer is used as colored (color) LVL, and parallel plywood using wood veneer is used after being painted or finished if necessary.

Examples will be described in detail below.

(Example 1) After dyeing a mangashiro rotary veneer with a thickness of 1.5 mm light brown, the obtained dyed veneer was hot pressed using a hot press roll at a pressure of 60 kg/cJ and a temperature of 200°C. did. The volume of the veneer after hot pressing was 70%. This was sequentially laminated with the fiber directions parallel to each other via an adhesive, and pressure molded to obtain a parallel plywood having a thickness of 30 mm, a width of 30.3 cm, and a length of 181.8 cm. The obtained parallel plywood had a significantly small warp of 3 mm, and was not a problem in practical use.

(Example 2) A Chinese sliced veneer with a thickness of 2.0 mm was hot pressed using a hot press roll at a pressure of 50 kg/cf and a temperature of 200°C. The veneer volume after hot pressing is 65
%Met. This was sequentially laminated with the fiber direction parallel to each other using an adhesive, and then pressure molded to a thickness of 30 mm and a width of 30.3 cm.
, length 181. 8cm parallel plywood was obtained. The obtained parallel plywood had a small warp of 5 mm, which caused no practical problems, and had excellent paintability.

(Example 3) After dyeing a mangashiro rotary veneer with a thickness of 1.0 cm in a brown color, the obtained dyed veneer was hot pressed using a hot press roll at a pressure of 50 kg/cJ and a temperature of 250°C. did. The volume of the veneer after hot pressing was 70%. These are sequentially laminated with the fibers parallel to each other using an adhesive.
A colored parallel plywood (color LVL) having a thickness of 10 mm, a width of 30.3 cm, and a length of 181.8 cm was obtained by pressure molding. The resulting parallel plywood had exceptional dimensional stability and was free from warping.

(Example 4) After dyeing a Celtis slice veneer with a thickness of 1.0 mm pink, the obtained dyed veneer was hot pressed using a hot press roll at a pressure of 30 kg/cJ and a temperature of 200°C. did. The veneer volume after hot pressing is 75%
Met. These were sequentially laminated with the fiber directions parallel to each other using an adhesive, and then pressure molded to a thickness of 15 mm and a width of 30.3 mm. cm
, 181.8cm long colored parallel plywood (color LVL)
I got it. The obtained parallel plywood had almost no warpage.

〔Effect of the invention〕

In this invention, when obtaining parallel plywood by laminating and pressing wood veneers with adhesive, the density of the parallel plywood is increased by pot pressing as the wood veneer, so the parallel plywood has a high density. It becomes hard and may warp or twist.
There are fewer and fewer items. Moreover, since it has a high density, paintability and processability are improved.

〔reference〕

Conventionally, in order to make the color change of decorative veneer as close as possible to that of natural veneer, the color distribution of the material veneer has been used. However, this method has a problem in that the color tone of the dyed veneer does not necessarily match the intended color tone.

In such a case, you can do the following:

That is, as shown in FIG. 4, first, a hygroscopic sheet 9 is attached onto a veneer 8 of material. The shape, size, etc. of the hygroscopic sheet 9 can be arbitrarily changed as desired. Next, the material veneer 8 to which the hygroscopic sheet 9 is attached is dyed. Staining is carried out using a pair of upper and lower roll coaters 10a rotating in the directions of arrows E and E' as shown in FIG. 5, for example.
, 10b are used to coat the dyes 11a and llb, and then heated in a steam atmosphere or the like. After dyeing, the hygroscopic sheet 9 is peeled off, and a dyed veneer 12 as shown in FIG. 6 is obtained. In the dyed veneer 12, the portion 13 from which the hygroscopic sheet is removed has a lower degree of dyeing than the portion 14 to which no hygroscopic sheet was attached from the beginning. The dyed veneers obtained by this method are then laminated with an adhesive, pressure molded, and sliced to obtain a decorative veneer rich in the intended color change (
Reference Example) After attaching a hygroscopic sheet to a veneer of material, a dye was applied and dyed in a steam atmosphere. After dyeing, the hygroscopic sheet was peeled off. Color difference Δ between the part of the dyed veneer from which the hygroscopic sheet was removed and the part to which the hygroscopic sheet was not attached from the beginning
E was 3.7.

The dyed veneers were laminated with an adhesive, pressure molded, and sliced. The obtained decorative veneer was rich in color tone changes.

[Brief explanation of the drawing]

Figure 1 is a perspective view of an example of dyeing wood veneer, Figure 2
The figure is a perspective view of an example of a hot press according to the present invention, Figure 3 is a side view of an example of a parallel plywood forming press according to the present invention, and Figure 4 is a veneer of material to which a hygroscopic sheet is attached. FIG. 5 is a side view of the dyed wood veneer, and FIG. 6 is a perspective view of the dyed veneer from which the hygroscopic sheet has been removed. ■...Wood veneer 2a, 2b...Roll coater 3
a, 3b... Dye 4a, 4b... Dyed veneer 5a
. 5b... Pot press roll 7... Parallel plywood agent Patent attorney Takehiko Matsumoto 0

Claims (3)

[Claims] (1) In obtaining parallel plywood by laminating and pressing wood veneers with an adhesive, the parallel plywood is characterized by using a wood veneer whose density has been increased by hot pressing. Manufacturing method. (2) The method for producing parallel plywood according to claim 1, wherein the wood veneer is dyed. (3) The method for producing parallel plywood according to claim 1, wherein the hot pressing is performed at a surface pressure of 30 to 50 kg/'cd and a temperature of 200 to 270°C.