JPS583802A - Manufacture of parallel plywood - 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 The present invention relates to a method for manufacturing parallel plywood in which O-tally lace veneers are laminated and pressure-formed with the fiber directions aligned, and the purpose thereof is to obtain parallel plywood with less warpage. To provide a manufacturing method for parallel plywood that can be used.

The present invention will be explained in detail below based on examples. First, from a log, a veneer (17) with a thickness of 1.0 to 3.5 is formed using a rotary lace, and this is dried until the moisture content reaches 5 to 10%. A veneer (2) with a second grain pattern of 0° 2-0.3 mm thickness is formed by slicing the 0-tally lace or veneer (2) from it to a moisture content of 5-10%.

Here, veneer +1) and veneer (Li) are determined by the specific gravity and the shrinkage rate in the fiber direction.Next, veneer (1)
5 to 35 plies, and the second veneer (2) is laminated with adhesive as 2 plies with the fiber direction aligned, and as shown in Figure 1, from the front and back of the laminated board. The second veneer (2) is placed on the second sheet.Then, it is 110-120"C16-i.

Hot pressure molding is performed at Kfcd for about 1 minute per 1 mm of thickness. As for the adhesive, use urea-based adhesive from 10 to
Use by applying 16 f/rep.

In this way, if the second veneer (2) of different materials is laminated at the same time with the same fiber direction, the shrinkage rate in the fiber direction is different from that of the veneer [11], which reduces the warping of the parallel plywood created. Moreover, since the fiber directions are the same, the beauty of the laminated cross section as parallel plywood is not impaired.

In particular, in the above embodiment, since the thickness of the second veneer (2) is thinner than that of the veneer (1), the second veneer (2) made of a different material stands out in the laminated cross section. It is something that never happens.

To give a specific example, a veneer with a thickness of 1 mm was formed using O-tally lace from benzyl jiter having a specific gravity of 0.60-0.72 and a shrinkage rate in the fiber direction of 5.1.
56 to 0.67, and the shrinkage rate in the fiber direction is 2°0. Sliced 0.56 to 0.67, and the plate thickness is 0.0.
A second veneer with a 3 mm grain pattern was formed. And 33 pieces of veneer, 4! J2 veneers were made into 2x5x veneers, and the second veneer was laminated on the third veneer from the front and back with the fiber directions aligned.

A urea-based adhesive was applied at a rate of 12 f/1, and was applied at a temperature of 110°C, a pressure of 6 Kfd, and a time of 30
When hot-press molding was carried out in minutes, the warpage (arrow height) at a width of 600tntnVc was 8 in the case without the second veneer.
There were 9 cases of WLrrL, but only 3wLWL, and the laminated cross sections of both cases were almost the same and beautiful. Incidentally, preferable results can be obtained by using a second veneer having a shrinkage rate smaller than that of the veneer.

Next, a second embodiment will be described. This is done by 0-tally lacing logs to form a veneer fl+ with a thickness of 1.0 to 3.5 myr, a width of 3 to 4 shaku, and a length of 6 to 13 shaku, and the moisture content is 5 to 5.
Dry until 10%. On the other hand, the peeled core of the raw wood obtained by rotary lacing the above veneer (1) is sliced to form a thin second veneer (2) with a thickness of 0.15 to 0.3 mm, and dried in the same manner. . Then 5 to 3 pieces of veneer (1)
The second veneer (2) is 2-ply, and urea-based adhesive is applied to one side of the 5-ply to 3-16V, and then laminated. At this time, as shown in Figure 2, the second veneer (!) is the 2nd to 5th veneer from the front and back, and the fiber direction is the same for all veneers (1). The second veneer (2) is arranged so that they are perpendicular to each other. After this, 10
Hot pressing is carried out at 0 to 120° C., 6 to 10 Kf/d, and approximately 1 minute per 1 mm of thickness. The obtained parallel plywood is made of a second veneer that is orthogonally pasted and has a shrinkage rate in a certain direction that is different from that of the veneer, so there is less warping and the second veneer is different from the veneer. Since it is made of the same type of wood and is thinner, it has a clean surface in the direction of the m-fiber and is easy to cut without impairing the characteristics of parallel plywood. In particular, since the peeled core after obtaining the veneer can be effectively used to make the second veneer, the yield is improved and the cost is reduced.

To describe a specific example, a rotary base made from Agatis with a thickness of 1. After creating a veneer of Omm and slicing the remaining peeled core to create a second veneer with a thickness of 0.3 rran, both were dried until the moisture content was 5 to 7%. , apply 12 yyf of urea adhesive,
A total of 35 plies of 33 plies of veneer and 2 plies of second veneer were laminated, and the second veneer was laminated as the third layer from the front and back so that it was pasted perpendicularly to the veneer, and the veneer was laminated as the third layer from the front and back. $'
d and ao were hot-pressed. The resulting parallel plywood without the second veneer has a width of 8rr for a width of 600 gourds.
Unlike LrrL's warpage (arrow height), there was only one gourd, and it did not detract from the beauty of the parallel plywood.

Next, a third embodiment will be described. The veneer is the same as in the first and second embodiments, but an artificial veneer is used as the second veneer. This artificial veneer is 1-3.5
A flitch is formed by laminating and pressing veneers of yawx thickness with the fiber direction aligned using an adhesive, and this flitch is sliced in a plane perpendicular to the laminated surface to reveal the seam of the laminated surface on the surface. It is expressed as a straight-grained wood grain. This second veneer was made into a 2-story veneer, and the veneer was made into a 5-35-story rye, and a 1-rea yarn picker was applied to each side at a coating amount of 10 to 16117 shaku 1 to make sure that all the fiber directions were the same. At the same time, the second veneer was laminated on the 2nd to 5th sheets from the front and back, and heated at 110 to 12 G'c, 6 to 10 degrees warmer, for approximately 1 minute per thickness. Heat and press. The artificial veneer, which is the second veneer, has a smaller shrinkage rate than the veneer because it has already been pressed once even though it is the same material as the veneer, so the resulting parallel plywood has less warpage. Since the fiber directions are aligned, the characteristics of parallel plywood, such as clean cut surfaces and ease of cutting, are not impaired.

Further, as a raw material for the second veneer, it is possible to use the peeled core of the raw wood after obtaining the veneer, and it is possible to improve yield, cost, and run.

To describe a specific example, a veneer with a thickness of 1.01 rtIL was created by rotary lace of agathis, and the remaining peeled core was further laced with 0-tally, and from the material veneer obtained, 0. 3- Create a second veneer with a thick straight grain pattern. In addition, since this second veneer is made using a raw material veneer with a peeled core, there are many defects in this material veneer, but these defective areas can be removed by padding or embedding. put. The accuracy at this time is ±ITrLrr
About L is sufficient. This is because it is not used as a surface layer, so it can be used even if some defects remain. The veneer is then dried to a moisture content of 5-7%, and 121 coats of urea-based adhesive is applied to the veneer, and the second veneer is coated with
Laminated with the fiber direction aligned so that the second veneer is located at the third veneer from the front and back, and heated at 110℃, 6111
/d, hot press molding was performed for 30 minutes. Note that the shrinkage rate of the veneer is 5 to 7%, and the shrinkage rate of the second veneer is 2 to 4%. The resulting parallel plywood without the second veneer has a width of 60 mm.
There was a warpage of just over 8mm compared to 0mm, whereas 4
There was only a warp less than WLfIL, and the characteristics as parallel plywood were not impaired.

The artificial veneer described in the above embodiments can be used to produce parallel plywood with a square grain pattern in the following manner. i.e. rotary raced i, o~3.5y
rm thick material veneer (dried until the moisture content is 5 to 10%) and applied vinyl acetate adhesive on one side to 10 to 161%.
Apply 7 shaku 8 coats and laminate the material veneers with the fiber direction aligned. The flitch (4) shown in Fig. 3 is formed by pressing with cold pressure for 12 hours or more, and the flitch (4) is sliced perpendicularly to the laminated surface. , 5? Artificial veneer with FLWL thickness (2f).Then, dry it again to a moisture content of 5 to 10%, align the fiber direction with a 5 to 35 lie, and
If the layers are laminated with a coating amount of 0 to 1617 R'' and heat pressed at 100 to 120°C and 6 to 1 (11/d) at a rate of approximately 1 minute per thickness, As shown in Figure 3(c), a parallel plywood (5) with a square grain pattern is obtained.It is preferable that 1 and m in the figure be equal.This parallel plywood (6) has a width direction and a thickness. While ordinary laminated veneers have a shrinkage rate of 5 to 7% in both directions, they only have a shrinkage rate of 2 to 4, and the warpage is less than 2 yrm for a radius of 600 trI!rL.Also, the cleanliness of the cross section is Not only is it no different from regular parallel plywood, but it has a straight-grained pattern on all sides, so it can be used in a wider range of applications.

To describe a specific example of this, agathis is
- 5 ~ 1 WarL thick material veneer obtained by tally lace
After drying to a moisture content of 7%, a vinyl acetate adhesive (Taizu I passed) Koniji CH107 (trade name) was applied at a coating amount of 12 f/R'' and 1000 sheets were laminated. A flitch was formed by cold-pressing for 12 hours with 600 yen.Then, this flitch was sliced perpendicular to the laminated surface to create an artificial veneer with a thickness of 1 fML. had risen to 17-2'0%, so we dried it again until it was 5-7%, then applied urea-based adhesive to this artificial veneer at 12 f/R'' and laminated it with 33 strands of 110 °C, 64. d. Hot pressing was performed for 30 minutes to obtain parallel plywood. As mentioned above, the warp of this parallel plywood is 2
It was less than WvrL and had a beautiful square grain pattern on all sides.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the stacked state of the first embodiment of the present invention, FIG. 2 is a front view showing the stacked state of the second embodiment, and FIG.
Figures -) to (e) are schematic diagrams showing the manufacturing process of parallel plywood with a four-sided straight grain pattern, where (l) shows a veneer and (ri) shows a second veneer. Agent Patent attorney Ishi 1) Chief Figure 1 Figure 2

Claims (1)

[Scope of Claims] (1) A large number of veneers formed by rotary lace are laminated with the wood fiber directions aligned, and the shrinkage rate in the same direction for the laminated veneer in the few sheets from the front and back of the laminated veneer. (2) A patent characterized in that a second veneer with a different grain pattern is used as the second veneer. Claim 1
Method for manufacturing parallel plywood as described in section. (3) A method for manufacturing parallel plywood according to claim 1, characterized in that the second veneer is a thin veneer of the same material whose fiber directions are orthogonally arranged as the laminated veneer. . (4) As the second veneer, an artificial veneer is formed by slicing the flitch obtained by laminating and pressing a large number of veneers with the fiber direction aligned and with a cutting plane perpendicular to the lamination plane and parallel to the fiber direction. A method for producing parallel plywood according to claim 1, characterized in that the fiber direction is the same as that of the laminated veneer.