JP2944792B2 - Manufacturing method of laminated material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a reinforced laminated material mainly composed of plant stems of grasses such as high altitude, corn, sugar cane and the like. More specifically, the present invention relates to a method for producing a laminated material used for building materials, furniture materials, heat insulating materials, sound absorbing materials, display materials, and various types of working materials.

[0002]

2. Description of the Related Art Conventionally, wood-based building materials, furniture materials, display materials, sound-absorbing materials, and various types of work materials include particle boards, fiber boards, and the like in addition to sawn wood, plywood, and laminated wood. Solid materials or foams of synthetic resins such as polystyrene, polyethylene, polyurethane, phenolic resin, melamine resin, and urea resin are used for display materials, sound absorbing materials, heat insulating materials, and the like. The materials used for these applications all depend on wood resources and petroleum resources. Although the sawn timber and plywood are wood itself and have high material strength and dimensional stability, there is a problem that the wood utilization rate (yield) is low because the portion having such characteristics is limited in wood.

[0003] On the other hand, a particle board or a fiber board is formed by mixing a small piece or fiber of wood with a synthetic resin adhesive and hardening it by heat and pressure to form a plate. These boards use wood and other raw materials effectively because they are made into small pieces or fibers, but on the other hand, because the cellulose fibers are finely cut, the mechanical strength and dimensional stability of the boards are reduced. There is a drawback that the property is poor. Wood materials such as sawn timber, plywood, laminated wood, particleboard and fiberboard, which are used in large quantities for building materials, are all made of natural wood, and as wood resources are becoming depleted in recent years, Due to the limited supply, it is now impossible to fully meet the strong demand in the future, and the price may rise significantly. Also, synthetic resin foams such as polystyrene, polyethylene, polyurethane and phenolic resin are lightweight, have good workability, and are excellent in heat insulation, so they are used for a wide range of applications as display materials and heat insulation materials. Because the resin depends on petroleum resources, it is threatened to secure a sufficient quantity in the future due to the problem of limited resources.

[0004] In order to cope with such a situation, the inventors of the present invention have abundantly existed in the world and reproduced every year, and it is difficult to dispose of them, such as Takarin, corn, sugar cane, etc. Patent application for a laminated material utilizing a straight portion of a grass stem of a grass family and a method for producing the same (Japanese Patent Application Laid-Open No. 63-107)
505, JP-A-1-280538). JP-A-63-10
The method described in the publication 7505 discloses a method for cutting a stem of a gramineous plant such as a high-strength, corn, sugar cane or the like in a fiber direction,
Rolling in an open state after performing core removal as necessary, forming a sheet-like material by arranging a plurality of rolling stems in parallel with each other, applying a known adhesive to the plurality of sheet-like materials, and then This is a method of laminating and pressing. Also, JP
The method described in -280538 discloses a flat stem as it is, without cutting or opening the high stem, or flattening by compression to form a flat stem, forming a flat stem layer by arranging a plurality of flat stems,
This is a method in which a known adhesive is applied to a plurality of flat stalk layers, and these are laminated and pressed. Laminates made by these methods become plates of any specific gravity, thickness, and dimensions and have excellent mechanical strength.

[0005]

However, in the former method, although extremely high mechanical strength and dimensional stability can be obtained, there are many steps such as incision, core removal, and rolling of a plant stem, and a predetermined thickness is obtained. In order to obtain one laminated material, many man-hours and a plant stem as a raw material are required, and there has been a problem that the production cost is high. In addition, the latter method, while the manufacturing cost is low, the mechanical strength is not higher than the laminated material manufactured by the former method, and if the laminated material is immersed in water or the laminated material contains moisture, There was a problem that the laminated material swelled and became thick. SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a versatile laminated material that requires low production cost, has extremely high mechanical strength and dimensional stability, is lightweight, and does not swell with water.

[0006]

In order to achieve the above object, as shown in FIGS. 1 to 4, a method for producing a laminated material according to the present invention comprises a method of producing a laminate 10a mainly composed of lignocellulose and a porous material. Rig on the plant stem 10 in a straight part having a pulp 10b
Liquid liquefaction liquid of cellulose or lignocellulose
And a plurality of the plant stems are arranged in parallel with each other, and the arranged plant stems are hot-pressed to heat-harden the heat-curing solution.

Hereinafter, the present invention will be described in detail. (a) Starting material As shown in FIG. 2, the material used for the laminated material of the present invention is a plant stem 10 having a structure having a skin portion 10a mainly composed of lignocellulose on the surface and a porous pulp portion 10b on the core. It is. Stalks such as Takarin, corn and sugar cane are typical. In addition, stems of other gramineous plants such as reeds, rice, barley and the like can be used. A plant stem is used without cutting a straight portion obtained by cutting a leaf or a hakama portion into small pieces. Compared to conventional bagasse boards and straw boards which are cut into small pieces and board-shaped,
A laminated material having extremely high bending strength while being lightweight can be obtained with a small number of steps. Before impregnating with the heat-curing liquid, the plant stem 10 is compressed by the compression rollers 11, 12 or the like without being cut open in the fiber direction as shown in FIG. However, it is preferable to divide the plant stem into two in the fiber direction because the heat-curing liquid permeates into the plant stem in a very short time of several minutes during impregnation. Various physical properties such as mechanical strength and dimensional stability of the laminated material provided with the cracks are not inferior to those without the cracks.

(B) Heat-curing liquid As shown in FIG. 4, the pre-treated plant stem 10 is impregnated with a heat-curing liquid 14. This heat-curing liquid is a liquid that hardens the plant stem by heating . Lignose is used for heat-curing liquid.
Lulose liquefied liquid or lignocellulose resinized liquid
I can do it. Here, the liquefied liquid of lignocellulose refers to a solution obtained by adding phenols and polyols to lignocellulose to liquefy lignocellulose. This liquefied liquid of lignocellulose can be used, for example, to remove leaves or hakama parts, or curved stems and offcuts that are not suitable for use, from plant stalks such as high-risk stems in the presence of phenols or the like. It is prepared by melting at a high temperature and a high pressure of 1 to 300 atm and 1 to 100 atm. Sulfuric acid, hydrochloric acid, phenolsulfonic acid,
By using an acid catalyst such as paraffinsulfonic acid, dissolution at 150 to 200 ° C. under atmospheric pressure becomes possible.
You. The lignocellulose resin solution is a resin solution obtained by converting a lignocellulose liquefied solution into a resin with an aldehyde compound or an isocyanate compound and dissolving the same in water or a solvent.

(C) Impregnation of the heat-curing liquid The heat-curing liquid of the present invention is 5 to 2 parts by weight based on the total dry weight of the plant stem.
Impregnation of 00% by weight. Although the plant stem is sufficiently impregnated at room temperature and atmospheric pressure, the heat-curing liquid may be impregnated by special heating or pressurizing or depressurizing. Heat impregnating liquid impregnation amount is 50
When the amount is more than the weight percentage, the heat-curable liquid oozes out when the sheet-like material is laminated, causing an adhesive effect, and the original amount of the adhesive used can be greatly reduced. When the heat curing liquid does not contain a high molecular weight component, the impregnation amount of the heat curing liquid must be 50% by weight or more, or an adhesive must be used. When the impregnation amount of the heat curing liquid is less than 5% by weight,
The effect of enhancing the laminated material, which is one of the objects of the present invention, cannot be sufficiently obtained, and particularly, the dimensional stability is extremely poor. 200% by weight
If it exceeds, the impregnation becomes difficult, and even if the impregnation is performed by an operation such as pressure injection, the strength of the laminated material is not further improved, and the dimensional stability is not further improved. As shown in FIG. 5, in order to remove the excess heat-curing liquid, the plant stem impregnated with the heat-curing liquid is squeezed into rolls 16 and 1.
It is preferable to leave the plant stem 20 impregnated with the desired amount through 7. After drying at room temperature to 200 ° C., the plurality of plant stems 20 are arranged in parallel with each other, for example, a plate-like or column-like laminated material is formed.

(D) Manufacture of a plate-shaped laminated material As shown in FIG. 1, when a plate-shaped laminated material is manufactured, plant stems 20 are arranged one by one to form a sheet-shaped material 30. A plurality of the sheet materials are superposed. At the time of forming the sheet-like material, the ends of all the arranged stems are tied with a thread 21 so that the plant stems are not dispersed, or temporarily fixed with an adhesive tape or a re-wet tape (not shown), or a thread-like or Apply glue in a band to bind all stems. The method of laminating the sheet-like materials is appropriately determined according to the purpose of use of the plate-like laminated material. In order to provide a uniform bending strength in all directions and prevent warpage of the laminated material, the sheet-like material 30 is arranged such that the plant stems 20 configured as shown in FIGS. Are stacked to form a laminate 40. When the bending strength in a specific direction is to be extremely high, FIG.
As shown in FIG. 4, a plurality of sheet-like materials 30 are stacked so that the plant stems 20 are arranged in the same direction. As shown in FIG.
May be made into a laminate 40 in which the plant stems constituting the other sheet-like material 30 are crossed. It is preferable that the plant stems are superimposed on each sheet so that the plant stems are orthogonal to each other so that the bending strength of the plate-like laminated material described later does not increase only in a specific direction. In addition, it is preferable to impregnate all the plant stems constituting the plate-like laminated material with the heat-curing liquid from the viewpoint of the strength and dimensional stability of the laminated material, but in order to further reduce the production cost, the plate-like laminated material is used. It is not necessary to impregnate a part of the constituent plant stems with the heat-curing liquid. For example, without impregnating all the plant stems constituting a part of the sheet-like material among the plurality of sheet-like materials to be superimposed with the heat-curing liquid, or by heat-curing a part of the plant stem constituting the sheet-like material. It is not necessary to impregnate the liquid.

When the amount of the heat-curing liquid impregnated in the plant stem is small or depending on the type of the heat-curing liquid, an adhesive is applied to the surface of the sheet-like material and laminated. The adhesive used at that time may be a known adhesive, for example, urea resin, melamine / urea co-condensation resin, phenol / melamine resin, phenol resin, phenol / resorcinol resin, resorcinol resin, isocyanate including aqueous polymer isocyanate adhesive Adhesives and tannin resins. It is preferable to use the above-mentioned resinified liquid of lignocellulose as the adhesive of the present invention, because the adhesive performance is improved due to the high affinity with the plant stalk, and the use ratio of the plant stalk can be increased to effectively use the plant stalk. These adhesives may use the above resins alone or in combination. The amount of the adhesive used is 1 to 50% by weight based on the total dry weight of the sheet. When the amount of the adhesive used is less than 1% by weight, the mechanical strength of the laminated material is significantly reduced, and when the amount used is more than 50% by weight, the cost is significantly increased as compared with the performance of the laminated material.

As shown in FIGS. 8 to 10, the laminated sheet 30 is subjected to temporary pressing as required to form a laminate 40, and both sides of the laminate 40 are sandwiched between metal plates 43. By hot pressing 42, at a temperature of 50 to 250 ° C.,
It is molded at a pressure of 30 kg / cm2. If the spacers 41 are arranged at the time of molding, the laminate 40 can be made into a plate-like laminate 50 having a predetermined thickness. Further, in order to increase the smoothness of the laminated material or obtain a highly accurate thickness, the laminated material is subjected to a surface treatment with a scraper, a planer, a sander or the like as necessary after molding. In addition, a single plate, MDF (M
Surface materials such as an edium density fiber board, a particle board, a metal plate, and a film can also be laminated.

(E) Manufacture of a columnar laminated material In a first method of producing a columnar laminated material, a plurality of plant stems in a straight line portion are arranged in parallel with each other to form a bundle, and this bundle is formed into a column by hot pressing. This is a batch method. As shown in FIG. 11, first, a plurality of plant stems 20 are arranged in the same direction, and are spread all over the bottom surface of a long and thin gutter-shaped female mold 44.
Form one. When the female mold 44 is longer than the plant stem 20, the plant stems are continuously arranged in the length direction and trimmed so as to fit in the female mold 44. After forming the first layer 51, the female mold 4
Similarly, a plurality of plant stems 20 are spread on the upper surface of the first layer 51 in 4 to form the second layer 52. Hereinafter, the third layer 5
Third, the fourth layer 54 and the like are formed. When the plant stems 20 are added and arranged side by side, the seam of the lower plant stem 20 and the seam of the upper plant stem 20 are shifted and stacked in order to increase the bending strength of the columnar laminated material. As shown in FIGS. 12 and 13,
After laminating the plant stems 20 in the female mold 44, the male mold 45 is inserted into the female mold 44, and the laminated plant stems 20 are compression molded.
The columnar laminated material 60 is made by this compression molding. When the amount of the heat-curing liquid impregnated in the plant stem is small, or depending on the type of the heat-curing liquid, an adhesive is applied to the layer surface in the same manner as in the production of the plate-like laminated material, and a plurality of layers are stacked.

The second method of manufacturing the columnar laminated material is shown in FIGS.
As shown in FIG. 16, this is a method in which a plurality of plate-like laminated materials 50 are stacked and bonded, and then cut in the arrangement direction of the plant stems. In this method, the plurality of plate-shaped laminated materials 50 are hot-pressed after applying an adhesive to both surfaces thereof. It is preferable that a thin sheet 56 such as a veneer or a plastic sheet to which an adhesive is previously applied on both sides is sandwiched between the laminated materials 50 and hot-pressed, so that the adhesive can be easily applied. The multi-layered laminated material 57 obtained by this molding is cut at a position indicated by an arrow P in FIG. Although this method can produce only prisms, it is simpler than the first production method using a mold. Moreover, the obtained columnar laminated material 60 has excellent dimensional stability and bending strength, and is suitably used as a building structural material.

Further, a third method of manufacturing a columnar laminated material is a method of continuously manufacturing as shown in FIGS. This manufacturing apparatus has driven rollers 71,
72 and drive rollers 73 and 74 are provided. Endless steel belts 75 and 76 are wound around the rollers 71 and 73 and the rollers 72 and 74, respectively. A gap is provided between the belt 75 and the belt 76. The gap between the rollers 73 and 74 is provided to an extent corresponding to the thickness of the columnar laminated material, and the gap between the rollers 71 and 72 is wider than this. Side walls 78, 7 are provided on both sides of the belts 75, 76.
9 is fixed. Numerous heating idle rollers 81 whose shafts rotate at fixed positions are disposed between the lower rollers 72 and 74, and a number of heating rollers whose shafts can move up and down are disposed between the upper rollers 71 and 73. A pressure roller 82 is provided. The width of the belts 75 and 76 and the width of the rollers 81 and 82 are substantially equal to the width of the finally obtained columnar laminated material.

A large number of plant stems 20 in a straight portion are bundled and continuously supplied on a steel belt 76. The large number of plant stems 20 introduced into the gap between the belts 75 and 76
5 and 76, compression-molded while being heated by the rollers 81 and 82, and become the columnar laminated material 60. When the amount of the heat-curing liquid impregnated in the plant stem is small, or depending on the type of the heat-curing liquid, an adhesive is applied to the surface of the plant stem in the same manner as in the first production method, and then supplied onto the belt 76. According to this method, an extremely long columnar laminated material can be easily mass-produced. In addition, a laminated material having an arbitrary shape can be obtained by variously selecting a shape of a mold at the time of hot pressing in addition to the above-described plate-shaped or columnar laminated material.

[0017]

When a heat-curing liquid is impregnated into a plant stem, the heat-curing liquid easily penetrates uniformly not only into the skin of the plant stem but also into the porous pulp of the core . For liquefied solution or a wide range of molecular weight components in the dissociation such as hydrolysis of the Li Diagnostics cellulose in the resin of liquid re Diagnostics cellulose heat curable liquid is generated, the medullary portion low molecular weight component and the high Both molecular weight components penetrate. At the same time, the low molecular weight component penetrates into the skin layer and shows the skin enhancement effect, and the high molecular weight component forms a resin layer on the skin surface layer and shows the adhesive effect simultaneously with the skin enhancement. . By using liquefied solution or the resin of liquid lignocellulose, there is also an effect that it is not necessary to either reduce the amount of adhesive or entirely the use of using during product layer. When a plurality of arranged plant stalks are hot-pressed, the adhesive dries, and the heat-curable liquid hardens and turns into a resin compound to form a reinforced laminate.

[0020]

Next, embodiments of the present invention will be described in detail with reference to the drawings together with comparative examples. <Example 1 > Before production of a laminated material, a high-cured stalk tree which is a heat-curing liquid
A fat solution was prepared. That is, the small pieces 70
0 g and phenol 300 g in 1 liter auto
Fill in clave and raise to 250 ° C with slow stirring
Warmed. The pressure inside the autoclave increases to 45 atm.
This condition is maintained for about 3 hours, and strips of high stalks are removed.
Dissolved in ethanol. Next, the liquefied liquid 80
0 g and 1000 g of 37% formalin in 1 liter volume
Into a three-necked flask, and stir with 40% caustic
Add 160 g of an aqueous solution and react at 80 ° C for 30 minutes.
I responded. After the reaction, the reaction product is quenched and water is added.
Then, a heat-curing liquid diluted to 10% concentration was prepared. FIG.
~ As shown in Fig. 5, a straight line cut to a length of about 30cm
Stem 10
A pinch roller 1 having an interval of about 60% of the diameter of 10
1 and 12 and finely split on the skin 10a of the stem 10.
A slit 13 was provided. This high spike is used as the heat-curing liquid.
Dipped for 5 minutes. The heat-curing liquid cracks as well as the skin 10a.
It penetrated into the pith 10b through the eye 13. This tall stem
Squeezing roll 1 with a distance of about 60% of the diameter of stem 10
Remove excess heat-curing liquid through 6 and 17 and leave room for 3 days
Dried at a high temperature to obtain a high sponge 20 impregnated with a heat-curing liquid
Was. As shown in FIG. 1 and FIG. 8, a heat-curing liquid was impregnated.
Arrange 17 tall stalks 20 parallel and closely to each other.
Row, stalk ends tied with thread 21 and sheet about 30cm wide
Three sheets 30 were produced. Next, three sheets 30
Isocyanate resin (Mitsui Toatsu)
(UR-4000) 50% aqueous dispersion in 10 g portions.
-After coating, the constituent stems 20
Three sheet-like objects 30 are stacked so as to be orthogonal to each other.
In total, a laminate 40 composed of three layers was produced. Then figure
As shown in FIG. 9, the laminate 40 was
Hot plate maintained at a temperature 0.99 ° C. was placed over support 4 1
, And the both sides of the laminate 40 are sandwiched between metal plates 43,
Hot-press forming at a pressure of about 4 kg / cm ² for 10 minutes
The layer material 50 was obtained.

<Comparative Example 1> A plate-like laminated material was obtained in the same manner as in Example 1 except that the heat-curable liquid of Example 1 was not used.

The plate-like laminate obtained in Example 1 and Comparative Example 1
After leaving the material in the room for 7 days, it is specified in JIS A 5908.
Normal music according to the specified particle board test method
Measurement of bending strength, bending Young's modulus, thickness swelling ratio, etc.
Was. Table 1 shows the results.

From Table 1, it can be seen that the plate-like laminated material is made of tall stalks.
With respect to Example 1, the bending strength of Example 1 was about
It was found that the modulus was 1.5 times higher and the Young's modulus was about 1.7 times higher.
Further, the water absorption and the thickness swelling ratio of Example 1 were much higher than those of Comparative Example 1.
The value was small. From the above, the product of Example 1
The laminate was found to have industrially superior properties.

[0024]

[Table 1]

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which a plurality of sheet-like objects are overlapped with a plant stem crossing each sheet-like material of the present invention.

FIG. 2 is a perspective view of a plant stem as its starting material.

FIG. 3 is a perspective view of a compression roller that compresses the plant stem to generate a crack in a skin portion.

FIG. 4 is a diagram of impregnating a plant stem with a heat-curing liquid.

FIG. 5 is a side view of a squeezing roller for removing excess heat-curing liquid from an impregnated plant stem.

FIG. 6 is a side view of a laminated body in which all the plant stems constituting a plurality of sheet-like materials are arranged in the same arrangement direction and are superimposed.

FIG. 7 is a side view of a laminated body in which the arrangement direction of plant stems constituting a part of a plurality of sheet-like materials is different from the arrangement direction of plant stems constituting another sheet-like material. FIG.

FIG. 8 is a side view of a laminate obtained by temporarily pressing the superposed sheet-like objects of FIG. 1;

FIG. 9 is a view showing a case where the laminate of FIG. 8 is hot-pressed.

FIG. 10 is a perspective view of the plate-like laminated material after the hot-press forming in FIG. 9;

FIG. 11 is a perspective view of a main part showing a situation where plant stems are arranged in a female mold to make a columnar laminated material.

FIG. 12 is a view in which a male mold is inserted into a female mold and hot-pressed to produce a columnar laminated material by a first manufacturing method.

FIG. 13 is a perspective view of the columnar laminated material after the hot pressing in FIG. 12;

FIG. 14 is a perspective view showing a state in which a plurality of plate-like laminated materials are overlapped in order to produce a column-shaped laminated material by a second manufacturing method.

FIG. 15 is a perspective view in which a plurality of plate-like laminated materials are bonded.

FIG. 16 is a perspective view of a columnar laminated material cut from multiple laminated materials.

FIG. 17 is a cross-sectional view of the apparatus for manufacturing a columnar laminated material based on the third manufacturing method, taken along line AA of FIG. 18;

FIG. 18 is a sectional view taken along line BB of FIG. 17;

[Explanation of symbols]

 Reference Signs List 10, 20, high stem (plant stem) 10a skin 10b pulp 13 fissure 14 phenolic resin aqueous solution (heat-cured liquid) 30 sheet-like material 40 laminated body 42 hot press 44 female type 45 male type 50 plate-shaped laminated material 56 Thin sheet 60 Pillar laminate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B32B 1/00-35/00 B27N 3/00-3/28

Claims (11)

(57) [Claims] 1. A skin (10) mainly composed of lignocellulose.
a) and a linear part of the plant stem (1) having a porous pith (10b).
0) to the liquefied liquid of lignocellulose or lignocellulose
Impregnated pressurizing thermosetting liquid is a resin of liquid (14), said plant stems arranged more parallel to one another and the plant stem which is arranged in hot pressing molding of the laminate to heat cure the heat curable liquid Production method. 2. Compression (1) of the plant stem by compressing the stem
3) After generating the method for producing a laminated material according to claim 1 wherein the impregnation of the heat curable liquid. 3. A plurality of plant stems are arranged in parallel with each other to form a sheet-like material (30), a plurality of the sheet-like materials are overlapped, and the stacked sheet-like materials are hot-pressed to form a heat-curable liquid. (14) the production method of the laminate of claim 1 wherein the heat curing the. 4. The method for producing a laminated material according to claim 3, wherein a plant stem constituting a part of the sheet-like material among all the sheet-like materials is overlapped so as to intersect with a plant stem constituting another sheet-like material. . 5. The method for producing a laminated material according to claim 3, wherein the plant stems constituting the sheet material are overlapped so as to cross each other for each sheet material. 6. The method for producing a laminated material according to claim 3 , wherein all the sheet-like materials are overlapped so that all the plant stems are arranged in the same direction. 7. The method for producing a laminated material according to claim 3 , wherein the adhesive is applied to the sheet, and then the sheet is hot-pressed. 8. A method for producing a laminated material of the main component of the adhesive according to claim 7, wherein the resin of liquid lignocellulose. 9. A columnar laminate (60) wherein all plant stems are arranged in the same direction to form a bundle, and then hot-pressed and integrated into a columnar shape.
The method for producing a laminated material according to claim 1, wherein 10. A laminated material (50) produced by the method according to claim 6, which is laminated and bonded so that the arrangement direction of the plant stems is the same, and then cut in the arrangement direction of the plant stems. A method of manufacturing a laminated material for obtaining a columnar laminated material (60). 11. A thin sheet (5) coated with an adhesive on both sides.
The method for manufacturing a laminated material according to claim 10, wherein the laminated material is adhered by interposing (6) between the laminated materials (50).