JPH02307701A - Manufacture of longitudinally joined decorative veneer sheet - Google Patents

Abstract

PURPOSE:To realize veneer, which has a little deformation, waviness and warpage even under the condition being very thin, and the hardness and brittleness of which is improved so as not to develop crack, by a method wherein finger joint part having crests and troughs in the form of zigzag is formed at both end edges in the direction of fiber of decorative veneer, to each unit one of which softening treatment is applied, so as to join a plurality of sheets of softening-treated decorative veneer by aligning the finger joint parts to each other. CONSTITUTION:Finger joint parts 2 and 2, the shapes of which fit exactly to each other, are formed at both end edges of decorative veneers 1 and 1 to be joined to each other by overlapping said edges with each other and cutting the overlapped part widthwise along a zigzag cutting line 4. After chips are removed, both the finger joint parts 2 and 2 are put together so as to be joined by plastering bonding aid tape 5 made of non-woven fabric tape or the like on the rear side of the joint. The bonding aid tape 5 may well be plasted on the top face side of the joint of the decorative veneers 1 or on both the front and rear sides of it under the condition that the tape applied on the front side is peeled off at use.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention is a vertically spliced decorative veneer used for edge pasting, wrapping, etc. The present invention relates to a method for manufacturing a decorative veneer sheet, which is generally made into a long piece by joining in the direction.

2. Description of the Related Art Conventionally, as this type of vertically spliced decorative veneer sheet, there has been known a sheet in which decorative veneers of a predetermined length are sequentially spliced vertically using a joining method called a finger joint. The decorative veneer sheet produced by this finger joint method is produced by punching out finger joints with continuous peaks and valleys in a zigzag pattern on both ends of the unit decorative veneer in the fiber direction. On a continuous backing sheet made of non-woven fabric, paper, woven fabric, etc., a large number of sheets are sequentially attached in the fiber direction while being adhered using an adhesive and aligning the finger joints so that they interlock with each other. Alternatively, the above-mentioned decorative veneer may be joined with auxiliary joining tape made of non-woven fabric tape or the like on the top or bottom surface of the fin card joint, or on both top and bottom surfaces.
It is manufactured to be seamed sequentially in the length direction.

Problems to be Solved by the Invention However, in the conventional method for manufacturing vertically spliced decorative veneers using finger joints, it is generally necessary to use relatively thick decorative veneers. Moreover, there were restrictions such as having to use straight-grained materials.

The reason is as follows.

That is, dry material must be used for the unit decorative veneer used as the material. This is because when wet veneers are used, it is easy to cut them to form finger joints, but if you try to join them as is, you will experience significant deformation such as cracks and waving due to drying shrinkage of the veneers themselves. This makes it difficult to properly match the peaks and valleys of the finger joints and join them, making it impossible to obtain a product of good quality. For this reason, dried veneer is used, but dried veneer is hard and brittle. For this reason, as shown in Fig. 7 in an exaggerated manner, especially for thin decorative veneers (11),
When the finger joint part (12) in which the peak part (12a) and the valley part (12b) are continuous in a zigzag shape is cut and formed, the finger joint part (12), especially the top end of the peak part (12a), etc. In addition to chipping (13) or cracking (14) on the sides of the peaks (12a), the thinner the material, the more unavoidable harmful deformation such as chapping and waving will occur. This makes it difficult to properly align and join the finger joints together. For this reason, even if the veneer is straight-grained, in order to produce a long decorative veneer sheet using the finger joint method, the thickness must be 0.3 mm or more, preferably 0.3 mm.
．． It is necessary to use one with a diameter of 4 mm or more.

In particular, with grained veneer, in addition to the inherent problem of difficult grain alignment, the above-mentioned chipping is more likely to occur, so decorative veneer with a thickness of at least 0.45 mm is generally used. be forced to.

For the reasons mentioned above, it is difficult to manufacture long decorative veneer sheets using the conventional finger joint method using extremely thin decorative veneers, and even thicker grained veneers are difficult to manufacture. Not only is this product not only expensive but also difficult to bend along some of the corners of the base material during use due to its lack of flexibility, and is prone to cracking. This led to similar problems.

The technical objective of this invention is to solve such problems.

Means for Solving the Problems This invention uses a decorative veneer as a material that has been softened by impregnating it with a soft resin, so that even if it is an extremely thin veneer, there will be less fraying, waving, and warping. This was developed with the focus on the fact that it can be made into a material with improved hardness and brittleness, making it less prone to chipping.

Accordingly, the present invention provides a method for softening unit decorative veneers by impregnating them with a soft synthetic resin, and then forming peaks and troughs in a zigzag shape at both ends of the softened decorative veneer in the fiber direction. The gist of this invention is a method for manufacturing a vertically spliced decorative veneer sheet, which is characterized by forming a finger joint part and aligning the finger joint part and the blade in an interlocking manner to join a plurality of softened decorative veneers. do.

Hereinafter, the present invention will be explained in more detail based on the accompanying drawings.

Unit decorative veneers (1) used as amulets include single veneers, laminated veneers, artificial square veneers, horizontal veneers, etc. with a thickness of about 0.2 to 0.8 mm. Those within the range of are used. Particularly preferably in the application of this invention, the thickness is 0.25
A range of about 0.45 m111 is used.

The unit decorative veneers are subjected to a predetermined softening treatment before being longitudinally spliced. This softening treatment involves impregnating an aqueous solution containing a soft synthetic resin as a treatment agent. Specifically, for example, polyethylene glycol, polypropylene glycol, polyvinyl alcohol, polyoxyethylene derivatives (such as polyoxyalkylene, alkyl ether, polyoxyalkylene, alkylphenyl ether, polyoxyalkylene fatty acid ester, etc.)
A soft synthetic resin such as, with an average molecular weight of 1,000 to 8
,000. Generally 3,000 to 5,000\
A solution having a concentration of about 20 to 45% is used as a treatment liquid, and the unit decorative veneer is impregnated by any method such as coating, dipping, pressure injection, vacuum injection, or vacuum pressure injection. To give a specific example of this impregnation treatment, it is immersed in a treatment solution with a liquid temperature of about 30 to 40 °C in a pressure vessel, and
It is preferable to inject under reduced pressure at 0.000 torr for 30 to 120 minutes and then maintain at normal pressure for 30 to 60 minutes. The amount of resin component impregnated by this softening treatment may be 12% or more in terms of solid content based on the dry weight of the decorative veneer (1), and if vermilion occurs, a sufficient softening treatment effect cannot be obtained. It is desirable that the content is preferably 15% or more.

The unit decorative veneer (1) impregnated with the soft resin component is then drained and dried to adjust the moisture content to 20% or less, preferably 15% or less. The draining process is optionally carried out to remove excess processing liquid adhering to the veneer and increase drying efficiency, and is carried out by passing the veneer one by one between narrowing rolls, or by drying the veneer as shown in Figure 6. As shown in the figure, the decorative veneer (1) is placed on the draining ramp (15) with a holding member such as a wire mesh (
This is carried out by standing upright while being held in place by 16) and leaving it for a predetermined period of time. In the latter case, changing the direction of the inclination of the veneer during the storage process will require a little longer overall storage time, but it will equalize the content of the treatment solution, making the subsequent drying process easier and reducing uneven drying. This is preferable in that it can prevent.

The drying process can be performed using any known drying process. For example, a method in which decorative veneers (1) are held one by one with a stainless steel or nylon mesh and passed through a blow dryer, a method in which each decorative veneer (1) is passed through a heat roll one by one, and a high frequency press dryer. This can be carried out by any means, such as a method using a high frequency vacuum dryer or a method using a high frequency vacuum dryer.

The softened decorative veneer (1) softened as described above is
Subsequently, this is vertically joined by a conventionally known finger joint method.

In this finger joint method, first, as shown in Fig. 1, ridges (2a) and valleys of different heights are formed on both ends of the softened decorative veneer (1) in the fiber direction. Department (
After forming a continuous zigzag finger joint part (2) with 2b) by punching or cutting, the adjacent decorative veneers (1) and (1
) and the above-mentioned finger joint portions (2) (2) are aligned in an interlocking manner, and both end edges are joined.

The steps from forming the finger joint part (2) to joining can be carried out continuously and automatically using a known finger joint machine. The end edges of the decorative veneers (1) (1) to be joined to each other are overlapped, and the overlapping portion (3) is cut along a zigzag cutting line (4) in the width direction.
- Cut the finger joint parts (2) (2) to form finger joint parts (2) (2) that perfectly match the shape of both end edges, and after removing the chips, put together both finger joint parts (2) (2), and As shown in the figure, an auxiliary joining tape (5) made of non-woven fabric tape or the like is attached to the back side of the joining part to complete the joining. The above-mentioned auxiliary joining tape (5) may be attached to the upper surface side of the joint part of the decorative veneer (1), or it may be attached to both the front and back surfaces, and the tape on the front side is peeled off and removed during use. Good as a thing. In addition, as a joining means, a finger joint part (
2) may be bonded by applying a pressure-sensitive adhesive (6) to a part or the entire surface of one or both end faces by spray painting, or as shown in Figure 4, The melt thread (7) may be disposed in a transverse manner on one or both sides of the joint part, spanning between both end plates, and welded and joined. Furthermore, as shown in FIG. 5, by applying a backing sheet (8) made of non-woven fabric, paper, synthetic resin sheet, etc. to the entire back side by applying hot or cold pressure,
The decorative veneers (1) (1) thereon may be substantially joined to each other. Furthermore, it goes without saying that two or more of the bonding methods shown in FIGS. 2 to 5 may be used in combination.

Decorative veneer sheet (A) manufactured by sequentially longitudinally splicing the above-mentioned finger joint method is generally rolled up into a roll for storage and transportation, and is also used. In this case, the film is rewound and used as a wrapping material for coating and pasting on the surface of a base material.

Effects of the Invention The method for manufacturing vertically spliced decorative veneer sheets according to the present invention basically adopts the finger joint method for joining unit decorative veneers together, so that the appearance of the joint can be improved. While making the joints less noticeable, the joints are increased and the joint strength is made relatively hard.In addition to the scales, the feed decorative veneer is pre-impregnated with soft resin. Since the decorative veneer is used after being subjected to a softening treatment, the decorative veneer itself is flexible and can be used without harmful deformation such as waving, fraying, or warping, or with very little deformation. Therefore, when forming finger joints on the softened decorative veneer, it is possible to prevent the top edges of the peaks from chipping, cracking, splitting, etc. This makes it possible to properly and closely align and join the parts. Furthermore, ultra-thin decorative veneers and boards that are impossible or extremely difficult to manufacture using conventional technology due to chipping or cracking of the finger joints, or overlapping or gaps due to misalignment of the joints. Good quality vertically seamed decorative veneers can be obtained by using thin decorative veneers such as straight-grained veneers with a thickness of 0.35 mm or less and grained veneers with a thickness of 0.45 mm or less, as well as with wide decorative veneers. Veneer sheets can be manufactured.

Therefore, the vertically spliced decorative veneer sheet itself has excellent flexibility and scales, so it can be stored in a rolled state, and it can be easily folded when used. It has the advantage that it easily conforms to the surface shape of the mating member to which it is attached, that is, the base material, and that defects such as cracking and lifting are less likely to occur in parts of the corners.

Examples Example 1 300 pieces of unit decorative veneer with a thickness of 0.3 mm, a width of 310 mm, and a length of 1.900 mm were prepared, and this was subjected to a softening treatment to reduce the average molecular weight. An impregnation treatment was performed by immersing the sample in a pressure vessel in an aqueous solution of polyethylene glycol 5,000 with a concentration of 25% and a liquid temperature of 35° C., followed by a vacuum injection treatment at 200 torr for 120 minutes, and then allowing it to stand at normal pressure for 120 minutes.

Next, the impregnated veneer was placed in an upright position on a draining slope, and the direction of the slope was reversed once during the process.
After draining by leaving it for a while, it was dried using a high frequency vacuum press dryer until the moisture content reached 15%.

The softened veneer obtained in this way has almost no warpage in the width direction, or even if it has warp, it has a width of 5 mm.
It had the following arrow height condition and did not have any deformation such as waving or unevenness. In addition, the content of polyethylene glycol component is 1 per veneer in terms of solid content.
It weighed 8 to 24 g.

Next, using the softened decorative veneer obtained above,
Using a known finger joint machine, the finger joint parts are punched out, the finger joint parts are butted together, and the auxiliary tape for joining is applied to the back side of the joint parts in order, and each decorative veneer is made. A long decorative veneer sheet I was obtained in which the fibers were successively longitudinally spliced in the fiber direction.

The above-mentioned auxiliary bonding tape is made of polyethylene-rayon mixed fiber non-woven fabric (fabric weight 189/m) with hot-melt adhesive applied dotted on one side. It was to be attached to the back side of the joint.

The obtained long decorative veneer sheet had defects such as chips, cracks, overlaps, and gaps at the finger joint joints, and was flexible overall and could be easily wound into a roll. .

Comparative example 1 Thickness 0.3 mm, width 310 mm % length 1.900 m
A decorative veneer with a moisture content of 85% was dried using a high frequency vacuum press dryer until the moisture content reached 15%.

The dried decorative veneer thus obtained has a height of 8 in the width direction.
It had irregular waving deformation of ~15 mm.

Therefore, next, using this dried decorative veneer,
Similarly, when joining was performed by the finger joint method using a finger joint machine, the mutual alignment of the finger joint parts of adjacent decorative veneers was poor, and there were some overlaps and gaps. Only a long decorative veneer sheet of inferior quality could be obtained that had some cracks along its length.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing how unit decorative veneers are joined by finger joints, Fig. 2 is a perspective view showing an example of cutting and forming operation of the finger joints, and Figs. 3 to 5 are how they are joined. Fig. 6 is a perspective view showing an example of the draining process, and Fig. 7 shows the occurrence of chips and cracks that may occur in the finger joints of decorative veneers in the prior art. FIG. (1)... Unit decorative veneer, (2)... Finger joint part, (2a)... Peak part, (2b)... Valley part,
(5)... Auxiliary tape for joining, (A)... Decorative veneer sheet. that's all

Claims (1)

[Claims] After applying a softening treatment to the unit decorative veneer by impregnating it with a soft synthetic resin, a finger joint portion having peaks and valleys in a zigzag shape is formed on both ends of the softened decorative veneer in the fiber direction. A method for manufacturing a vertically spliced decorative veneer sheet, characterized in that a plurality of softened decorative veneers are joined by aligning the finger joints in an interlocking manner with each other.