JPS63128903A - Manufacture of laminated wood - Google Patents

Abstract

PURPOSE:To make it possible to form a wood with any width, thickness and length by a method wherein a large number of raw materials are compressed so as to parallel a large number of their fibrous elements side by side and at the same time cover with powder adhesive and, under the above-mentioned state, the raw materials are pressure-molded into an integral body with the required shape. CONSTITUTION:Raw materials are boiled or steamed in response to kind of tree and state (dry wood or green wood), when necessary in pretreatment process. Fibrous elements are formed by compressing the raw materials. In this case, since the compression of raw material at a stretch causes to distruct fibers, the gradual compression of raw material is preferable. The continuous production of fibrous elements is done with a roller press. However, as for short raw materials, preferable production of fibrous elements is to treat the raw material by batch with the well-known pressing device. A large number of obtained fibrous elements 10 are dried by hot air or steam. Next, a large number of the dried fibrous elements 10 are cut to lengths, when necessary. Next, the fibrous elements 10 are covered with powder hot-melt adhesive 15 (the well-known adhesive for bonding woods). Under the state being adhered with the adhesive as just mentioned above, the fibrous elements are pressure-molded.

Description

[Detailed description of the invention] The present invention aims to solve the following problems.

(Industrial Application Field) This invention relates to a method for manufacturing laminated wood.

(Prior art) A method of obtaining laminated wood of a desired shape by cutting raw material wood thinly to form thin plates, then compressing and gluing a large number of thin plates in a lined-up state is a method of obtaining laminated wood of a desired size. Moreover, it is possible to obtain wood with properties similar to ordinary wood, but there is a problem in that the raw material mentioned above must be thick enough and long enough to be processed into thin pieces. .

Therefore, in order to eliminate the above-mentioned conventional problems, the present inventor utilized any type of wood as a raw material, regardless of its thickness or length, compressed it to form continuous reticular fibers, and Previously we have provided a method for producing laminated wood that can be glued to obtain a laminated wood as described above.

(For example, Japanese Patent Application No. 107877/1982, Japanese Patent Application No. 60/2013)
(Refer to No. 99432) However, in the above manufacturing method, when a liquid adhesive is used to bond a large number of continuous Vt network fibers together, the network fibers soften and are overlapped and compressed, so that the specific gravity of the molded product decreases. There was a serious problem. Furthermore, because the adhesive is a liquid, its pot life is limited. In addition to this, various problems such as those described below also occurred. That is, (a) when a liquid adhesive application method using a roll coater is used, there is a problem in that fibers adhere to and wrap around the roller, and it is extremely time-consuming to remove or organize the wrapped fibers.

(b) When applying adhesive by curtain call means, it is necessary to use a highly viscous material to spread the adhesive in a film, which increases the amount of adhesive used and makes it uneconomical. There was also the problem that the weight of the finished product was also heavy.

(c) When dipping is used, the adhesive penetrates into many fibers themselves or between the fibers, so there is a problem that a large amount of adhesive is required, making it uneconomical. When compression molding is performed, a large amount of water thin air is generated, resulting in defective products (commonly referred to as punctures).

(d) Furthermore, in the method of applying liquid adhesive by spraying, there is a lot of loss due to scattering, and the adhesive adheres only to the surface of the fibrous elements, making it difficult to penetrate into deep areas. Therefore, there is a problem of poor adhesion during pressure molding.

Furthermore, if a large amount of adhesive is applied to prevent this, problems similar to those caused by the above-mentioned dipping method will occur.

(Problems to be Solved by the Invention) In order to eliminate the above-mentioned problems, the present invention provides a manufacturing method in which continuous reticular fibers are sprinkled with a powdered adhesive and compressed and bonded.

The configuration of the present invention is as follows.

(Means for Solving the Problems) The present invention takes the measures as described in the claims above, and its effects are as follows.

(Operation) A large number of raw materials are compressed to obtain a continuous network fiber, that is, a large number of fibrous elements. Next, a large number of these fibrous elements are arranged so as to be lined up, and a powdered adhesive is applied to them, and then they are pressure-molded into a desired shape and integrated to obtain a laminated wood.

(Example) Examples of the present invention will be described below based on the drawings. First, prepare the raw materials. As this raw material, any tree species and any shape of wood can be used. For example, raw wood such as thinned wood, short wood, bent wood, or defective wood, backboard of sawn lumber, wood ends, etc. can be used. It goes without saying that the above-mentioned thinned wood can be used if it is well-shaped, but it can also be used if it is a small-diameter tree and has many defects such as bending (when thinning in a plantation, it is mainly because inferior water is thinned out). There are many plants with the following drawbacks. Such materials have low marketability as materials and are cheap, and because they cannot afford the cost of cutting and transporting them, they are left unused in the body.) can also be used. Furthermore, the forestry industry in our country is IIi! ! Post-planted forests are now 15 to 25 years old and are entering the thinning period.The number of forests targeted for thinning reaches 4 million ha nationwide, and 300,000 hectares of standing timber are thinned annually, with an area of 6 million m2 of standing timber.
3 (material equivalent: 4 million m3). Although up to one-third of such thinned wood is left in the body as mentioned above, it is possible to utilize thinned wood. On the other hand, imported wood is often made of large-diameter wood, but the length of the material is mostly irregular, and when cut to a regular length, there are many short pieces of 2 meters or less. It is possible to use such scraps. In addition to the main product, lumber produces by-products such as backboards and wood ends, and it is also possible to use such by-products.

Next, among the above raw materials, regarding logs with a diameter of 10 cm or more, backboards and sawn timber products with a thickness of 10 cm or more,
As shown in Fig. 1 (a) and (b), the raw material l is divided into two or more parts according to their size using the splitter 2, and
Conditions as shown in c), (d), and (e) [set to 1]. In addition, the raw materials mentioned above are determined by their tree species and condition (dried wood,
If necessary, boiling or steaming is performed as a pre-treatment step, depending on the type of wood (green wood). Boiling or steaming (80°C to 200°C) softens the wood because the lignin that binds the wood fibers is thermoplastic. When compressed in this state, it can be easily crushed (untreated, a pressure of 100 kg/cd or more was required, but as a result of treatment, a pressure of 1/3 to 115 is sufficient).

Boiling and steaming times vary depending on the cross-sectional size of the Byakko material.

The raw material is then compressed to form a fibrous element.

In this case, compressing the raw material all at once will cause fiber breakage, so it is better to compress it gradually.A roller press is preferred for continuous production of fibrous elements, but short and small raw materials can be processed in batches using well-known press equipment. It's good to do that.

The processing using the roller press is carried out by inserting the raw material 1 between a pair of rollers, which are illustrated as compression members, as shown in FIG. In this case, it is preferable to prepare a plurality of pairs of rollers with different mutual gaps, as shown by reference numerals 3 and 4.5, so that the raw material 1 is gradually compressed between these rollers. The final stage 5
Generally, the gap between the pair of compression rollers may be about 3 pieces or less, but it may be about 0.5 to 1 day to obtain a fibrous element in which the fibers are loosened better.

Next, since the wood compressed as described above has a large number of fibers overlapping each other, this is spread out in the width direction to make it thinner. The operation is carried out by the following methods (a) to (C) depending on the species of wood and the shape of the compressed wood.

(a) As shown in Fig. 3, the compressed wood is placed between a pair of rollers 7.
In the figure, it is inserted in a direction perpendicular to the paper surface. By passing the wood between such rollers, a large number of fibers are spread out in the width direction, and as shown in FIG.
A fibrous element 10 is completed in which the fibers overlap each other in a net shape while maintaining their arrangement in substantially parallel or substantially constant directions.

(b) As shown in FIG. 4, the compressed wood 1'' is moved between a pair of rollers 8.8 which are being rotated by a drive device not shown, and the shaft 8a of the roller 8 is connected to the fibers of the wood 1''. angle α (e.g. 10” to 45
°) Insert it so that it is in an inclined state. As a result, the wood 1 is spread out in the width direction, and a fibrous element 10 as shown in FIG. 6 is completed.

(C) Roller 9 rotating at high speed as shown in Figure 5
When the compressed wood 1'' is inserted in the direction Y perpendicular to the fiber direction Since the fibers are different from each other, a large number of fibers 10a of the wood passing through these rollers are loosened in the direction of the arrow Y, resulting in a fibrous element 10 as shown in FIG. The method shown in Fig. 5 is based on the method shown in Fig.
It is suitable for cases where the length (width direction) is long.

The pair of rollers 9a and 9b may have different diameters, and by rotating them at the same rotational speed, different circumferential speeds may be obtained.

The large number of fibrous elements IO obtained as described above is then dried with hot air or steam.

Next, the dried fibrous elements 10 are cut into appropriate lengths as needed. For example, as shown in FIG. 7, a large number of fibrous materials to which adhesive has been adhered are placed on a mold 11 equipped with heating means, as shown in FIG. The elements 10 are placed in a state in which the fibers of each element are aligned in a substantially constant direction (or the fibrous elements 10 may be arranged vertically, horizontally, or diagonally randomly), and a mold 12 equipped with a heating means is placed. It is lowered toward the forming die 11 and heated and pressed between them. As a result, the bundle-shaped adhesive (I) melts and exhibits adhesive properties, forming a large number of fibrous elements 10.
are glued together. This completes the oriented laminated wood. In the case of manufacturing as described above, since the network-like continuous fibers are dried as described above, the portions where the fibers overlap and are crushed are swollen, and the fibers are also hard.

For this reason, spaces are created between the fibers, and the powdered adhesive can effectively penetrate between the fibers. Furthermore, as mentioned above, since the fibers are hard, there are voids between the fibers even when the fibers are pressed together under heat, so that a molded product with a low specific gravity can be produced.

Improved wood types with low specific gravity (less than 0.65), medium specific gravity (0.65 to 0.8), and high specific gravity (0.81 or more) can be produced depending on the pressure applied during pressurization. Low specific gravity materials can be used as insulation and sound absorbing materials, medium specific gravity materials can be used as building materials, furniture materials, and packaging materials, and high specific gravity materials can be used as structural materials for construction. I can do it.

Next, since the heat-melting powder adhesive described above does not change without being heated, it has no relation to pot life and can be used freely at any time.

Next, the means for applying the powdered adhesive to the fibrous element 10 obtained and dried as shown in FIG. 6 will be further explained. There are various means as follows.

(a) In the process of transporting a large number of fibrous elements 10 on a conveyor or the like, a powdered adhesive is sprinkled over them. Then, since the adhesive is in powder form, it not only adheres to a large number of fibers 10a as indicated by reference numeral 15 as shown in FIG. The powdered adhesive that has gone around to the parts that are in the same state is mechanically caught and adhered to each fiber 10a.
The powdered adhesive 15 is adhered to the entire circumference. Incidentally, the powdered adhesive may be sprinkled on a plurality of fibrous elements arranged on the mold 11 as shown in FIG. 7.

(b) Due to the nature of the fibrous elements 10 or powder adhesive, it is difficult for the adhesive to get on the fibers 10a (slip off).
If this is the case, a small amount of water or paraffin is sprinkled over a number of fibrous elements as a pretreatment. Then, in this state, powdered adhesive is sprinkled as in the case (a) above.

(c) providing a room in the middle of the transport route of the fibrous elements;
The inside of the chamber is filled with a powdered adhesive in a suspended state. By passing the above-mentioned fibrous elements or the fibrous elements pre-processed in (b) through such a chamber, a large number of A large number of fibers 10a in the fibrous element IO
As shown in FIG. 8, powdered adhesive 15 is adhered to the peripheral surface of.

(d) A large number of fibrous elements are placed in a sealable container or chamber, and the interior of the container or chamber is then depressurized. Thereafter, the powdered adhesive is injected into the container or chamber along with air or any other gas. Then, the interior of the container or room is filled with powdered adhesive in a floating state, and the adhesive adheres to the surrounding surfaces of a large number of fibers 10a, as shown in FIG.

Next, as the above-mentioned powdered adhesive, well-known adhesives such as urethane, phenol, melamine, and urethane adhesives can be used, and the wood is placed under high temperature and pressure using steam, and then rapidly depressurized to turn it into wood powder. Adhesive powder for filling gaps between laminated wood pieces formed by drying and pulverizing wood powder (for example, Japanese Patent Application No. 1983-397)
No. 49) may be used alone or in combination depending on the purpose.

The adhesive powder described above may also be used as an extender.

Next, to give another example of manufacturing laminated wood, if a liquid adhesive is applied to the reticulated continuous fiber elements in the surface layer of a molded product, and a powder is applied to the elements in the core layer and heat compressed, the surface layer The surface of the molded product is smooth and the core layer has voids. Such a molded product has a relatively light specific gravity and a smooth surface. In addition, in the case of this manufacturing method, the water in the surface layer turns into steam and enters the core layer, improving heat conduction, so the compression time can be shortened.
Since the core layer is dry, it has the advantage of being less prone to punctures even when steam enters.

Next, the above-mentioned means of pressure forming can be carried out by using a well-known method when manufacturing this type of wood. Pressure forming may be performed continuously by passing the material continuously between a pair of upper and lower rollers. Further, as described above, a large number of fibrous elements are arranged so that the fibers are aligned in a substantially constant direction, and then a large number of fibrous elements are arranged on top of the fibrous elements so that the fiber directions intersect (for example, orthogonally) with the above. By repeating this process multiple times, it is possible to create a product with average strength in the vertical and horizontal directions, similar to plywood.

In addition, the arrangement of each roller in FIG.
Shift a, 4a, and 5a to the right, respectively, and remove rollers 3b and 3a.
, 4b, 4a, 5b, and 5a may be arranged in a staggered manner in this order.

Next, a piece of the fibrous element 10 that is difficult to use for producing the above laminated wood (for example, length 10 (J or less)) may be used to produce a different type of wood (board) than the above. In this case, the number of scraps as described above is placed in the mold 1 in the same manner as shown in Fig. 7.
1, and apply any adhesive such as liquid or powder thereon. As the application means, any of the methods described above may be used. Thereafter, the adhesive-coated material is pressure-molded in the same manner as in the above case, thereby completing a different laminated wood material. In addition to the above-mentioned scraps, raw materials for this kind of production include small wood chips (chips) that are not suitable for producing fibrous elements as shown in Figure 6 above.
Loosen it using any pressure means such as a roller or press,
Fibrous elements made thereby may also be used.

Furthermore, using another piece of wood made as described above as a core, a large number of fibrous elements as described above (as shown in Fig. 6) were arranged on the front and back sides of the core, with the fibers having directionality, and these were further processed. It can also be made into a plate material by pressure bonding.

(Effects of the Invention) As described above, in the present invention, a large number of raw materials are compressed by a compression member to form a large number of fibrous elements in which a large number of fibers are mutually loosened,
Since a large number of these fibrous elements 10 are pressure-molded, it has the advantage that wood having arbitrary width, thickness, and length dimensions can be formed.

Furthermore, even if it is possible to obtain wood in the preferred form as described above, the raw material is compressed to form a fibrous element in which the fibers are loosened together, and this is then molded as described above. The above-mentioned raw material wood can be of any length, long or short, thick or thin in diameter, and the above-mentioned thinned wood, offcuts, backboards, wood ends, etc., which were previously wasted, can be used. It has great utility in the industrial field, where it can be used to a great extent.

Furthermore, the wood formed as described above has many small gaps between the fibers in the wood due to the pressure molding of a large number of fibrous elements as described above, and as a result,
In addition to having high heat insulation properties, it also has the advantage of being extremely lightweight and easy to handle.

Furthermore, since the manufacturing method of the present invention uses a powdered adhesive, when a large number of fibrous elements are bonded together by pressure, the large number of fibers in the large number of fibrous elements maintain their hardness. It has the advantage that it can be bonded as it is (without the fibers becoming soft due to moisture content, as is the case when using liquid adhesives). This has the effect of allowing a large amount of space to be left and allowing the manufacture of very light products.

Furthermore, since a powdered adhesive is used, the adhesive adheres evenly to the entire large number of fibers. This means that a large number of fibers can be evenly bonded throughout the molding process, resulting in a high-quality product.

There are features that can be used.

[BRIEF DESCRIPTION OF THE DRAWINGS] The drawings show an embodiment of the present application, and FIG. 1 is a diagram for explaining the state of dividing the raw material, FIG. 2 is a diagram showing the state of roller pressing the raw material, and FIG. 5 to 5 are views showing a means for stretching the compressed raw material in the width direction, FIG. 6 is a perspective view of a fibrous element, FIG. 7 is a perspective view showing an example of a pressure forming means, and FIG. The figure is an enlarged cross-sectional view showing a state in which powdered adhesive is attached to fibers. l: Raw material, 10: Fibrous element.

Claims (1)

[Claims] A large number of raw materials are compressed by a compression member to form a large number of fibrous elements in which a large number of fibers are loosened together, and then a powdered adhesive is attached to the large number of fibrous elements. A method for manufacturing laminated wood, which comprises pressurizing and forming the wood into one piece.