JPH0752113A - Multi-layered structural body and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a multi-layered structural body, useful for the replaced material of wood, by a method wherein at least one surface of the outermost layers of an integrated body, having an integral structure made by combining a cured layer, constituted by curing a mixture containing crushed or split used paper and thermosetting resin, with the surface material layer arbitrarily, is made by the surface material layer. CONSTITUTION:A surface material is arranged under a condition that the same is contacted with both surfaces or one surface of a precursor, formed of a mixture containing at least used paper, fibrous substance, added if necessary, and a thermosetting resin, the laminated body of the precursor or a multi-layered precursor, in which the surface material is arranged between a plurality of precursors. The structural body is heated by ventilating heating, oven heating or the like or the precursor is cured by heating and pressurizing through a press machine, a draw-forming machine, an extruder or the like, then, the precursor is integrated with the surface material. According to this method, not only a plate, having a multi-layered structure consisting of the surface material and cured body, but also a continuous plate having a curved surface, can be formed and, further, the surface material can be manufactured by bonding a soft surface finishing material through an adhesive agent, if necessary.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-layered structure and a method for manufacturing the same, and the multi-layered structure is used for building materials such as floor siding materials, wall materials, civil engineering materials such as formwork materials and scaffolding materials, and wood. It is preferably used as a wood substitute material for packing frame materials and the like, conveying pallet materials and the like, and furniture for lining materials and the like.

[0002]

2. Description of the Related Art In recent years, from the viewpoint of protection of the natural environment and depletion of wood resources, etc., there is a worldwide review of wood resources, and artificial wood as a substitute for natural wood,
Alternatively, development is being carried out aiming at resource saving or effective utilization such as quality improvement by chemical modification of wood or addition of new functions. On the other hand, contrary to such efforts, an extremely large amount of paper is consumed due to the popularization of OA equipment, the increase in newspapers, magazines, books, etc., and excessive packaging. Although some of the unnecessary paper generated by these is collected and recycled, most of it is disposed of, and from the perspective of effective utilization of wood resources, such waste paper The advent of reuse technology is extremely useful and is strongly desired by many industrial fields.

[0003]

Therefore, the present invention has been made by paying attention to the above-mentioned circumstances, and it is a multi-layered material which makes effective use of waste paper which has been conventionally disposed of and is particularly useful as a wood substitute material. It is intended to provide a structure.

[0004]

In order to achieve the above object, the present invention provides a hardened layer and a face material layer obtained by hardening a mixture containing waste paper that has been crushed or defibrated and a thermosetting resin. The present invention provides a multi-layer structure having an integrated structure having any combination of the above, wherein at least one surface of the outermost layer is a face material layer.

The waste paper used as a constituent of the cured product may be either a natural fiber type or a plastic type, but is preferably a natural fiber type paper such as newspaper, magazine paper, corrugated paper, Examples include pulp paper, wrapping paper, recording paper, and the like. When recycled waste paper is reused, it is defibrated or crushed to achieve a state close to it in order to improve the mixing property with the thermosetting resin and fibrous substance described later to obtain a uniform structure. To use.

Further, fibers other than waste paper can be added as a reinforcing material depending on the required characteristics and applications when using waste paper as a wood substitute material. Such additional fibrous materials include, for example, inorganic fibers such as glass fibers, carbon fibers, ceramic fibers, rock wool fibers, organic fibers such as aramid fibers, nylon fibers, vinylidene chloride fibers, polyester fibers, and phenol fibers. Fiber, or metal fiber such as stainless fiber, aluminum fiber, copper fiber,
Alternatively, a strand obtained by bundling these fibers, a roving in which the strands are aligned, and the like are included.
These may be used alone or in combination of two or more. The amount of the fibrous substance to be used is appropriately selected depending on the required characteristics and application, but generally, the proportion in the cured product is 1 to 50% by weight, preferably 5 to 30% by weight.

The waste paper that has been defibrated or crushed is bound with a thermosetting resin to form a constituent element of the multilayer structure (hereinafter referred to as "hardened paper waste"). The thermosetting resin has a function of forming and integrating the disintegrated or crushed waste paper into a united body and a function of imparting strength to the structure. Examples of the thermosetting resin include phenol resin, melamine resin, urea resin, epoxy resin, and unsaturated polyester resin, but among them, heat resistance,
From the viewpoint of flame resistance, it is preferable to use a phenolic resin, for example, a novolak type phenolic resin which is not curable by itself but is cured by a cross-linking agent such as hexamethylenetetramine or a self-curable phenolic resin described later. Or a self-curable phenol resin typified by an alkali resol type, an ammonia resol type, a benzylic ether type, and a novolak type having a methylol group.

The mixing ratio of the thermosetting resin to the preceding waste paper or the waste paper and the fibrous substance is appropriately selected according to the required characteristics and application, but in general, the thermosetting resin / waste paper or The weight ratio of waste paper to fibrous substance is 5/95 to 80/20, preferably 20/80 to 60/40. The reason is that if the weight ratio is less than 5/95, there is a problem in strength, and if it exceeds 80/20, the cost is increased, which is not preferable.

A cured waste paper obtained by defibrating or crushing waste paper with a curing resin has a certain degree of mechanical strength, nail retention and saw workability, drillability, nailability and other workability. However, it is still insufficient to be used as a wood substitute, and there is a problem in terms of aesthetics. However, according to the study of the present inventors, by combining a cured paper waste with a face material, it is possible to provide sufficient strength or processability and aesthetics suitable for various wood-related applications,
Therefore, it has been found that even recycled products of waste paper can be obtained which are sufficiently practical as wood substitutes and the like.

As such a face material, for example, a single plate,
Plywood, decorative plywood, laminated wood, particle board, wood board such as fiber board, acrylic board, plastic board such as vinyl chloride corrugated board, gypsum board, inorganic board such as rock wool board, aluminum board, zinc iron board, Metal plates such as embossed steel plates, laminated plates (eg, glass, cloth, paper, etc.), reinforced plastic plates such as FRP, foamed resin plates such as polyurethane foam, phenol foam, polystyrene foam, polyethylene foam, or these A plate having an embossed surface, a holed surface, a design surface having fine particles attached thereto, or the above-mentioned inorganic fiber or organic fiber non-woven fabric or woven fabric is used. These may be used alone or in combination of two or more.

In the present invention, the reason why the face material is used as at least one surface of the outermost layer of the multi-layer structure is to impart further strength to the cured paper waste to enhance its practicality as a wood substitute material. There are certain surface materials,
For example, a wood board, a non-woven fabric or a woven fabric or a combination thereof is used for the workability of the waste paper cured product itself, for example, workability such as chipping during sawing, chipping of the hole periphery during drilling, especially sawing workability, nailing. It is extremely effective in improving chipping, cracking and nail holding power at the time of hammering, or deformation, such as warpage due to environmental changes such as temperature and humidity. Moreover, even if the thickness of the face material to be used is 10 mm or less, preferably 5 mm or less, the above object can be sufficiently achieved, which can contribute to the saving of wood resources. In addition, foamed resin boards are preferably selected in the field where lightness is important.

As described above, by combining the cured waste paper and the appropriate surface material, the cured waste paper alone is not sufficient. For example, for building materials such as floor abandonment materials and wall materials, formwork materials, It has become suitable for use as a wood substitute material for civil engineering such as scaffolding, packaging for wooden frame materials, transportation for pallet materials and furniture such as lining materials. However, in addition to the outermost surface material, the surface material may be an intermediate layer of a plurality of waste paper cured products, for example, a woven fabric or a non-woven fabric may be used to impart a desired reinforcing effect and deformation resistance.

The waste paper cured body and the face material may be bonded together when the waste paper cured body is cured, or may be adhered with an adhesive after or at the time of curing. According to the present invention, as shown in the perspective view of FIG. 1, a cured body 1 formed by binding and curing waste paper or waste paper and a fibrous substance with a thermosetting resin.
And face materials 2 and 3 integrally joined to the upper and lower surfaces of the cured body 1.
Provides a multilayer structure configured in a sandwich structure.

Further, as shown in the perspective view of FIG. 2, waste paper or waste paper cured bodies 5 and 6 formed by binding and curing waste paper and a fibrous substance with a thermosetting resin, and the waste paper cured bodies 5 and 6 There is provided a multilayer structure having a structure in which a face material 7 interposed between the waste paper hardened bodies 5 and 6 and face materials 8 and 9 placed on the upper and lower surfaces of the waste paper cured bodies 5 and 6 are integrally joined. A method for manufacturing the multi-layer structure of the present invention will be exemplarily described based on a plate-shaped three-layer structure showing one embodiment. One of the methods is a wet papermaking method, and first, a waste paper slurry that has been previously treated with a pulper, a Henschel mixer, or the like, and a fibrous substance if necessary, and a powdery or fibrous, preferably fibrous heat After uniformly stirring and mixing the curable resin in the mixing tank, it is made up with a round-net or fourdrinier papermaking machine, and then dehydrated by depressurization or press filtration to form a wet precursor. To do. In this step, a curing agent that imparts thermosetting properties depending on the resin used, or a curing accelerator that improves thermosetting properties is added and mixed, or a wet precursor after papermaking is spray impregnated with these. You may fix it. Further, the wet precursor is preferably dried to a desired moisture content by, for example, hot air ventilation or oven heating.

As a method for forming such a precursor, the above-described wet papermaking method is preferable, but waste paper or waste paper treated with an appropriate pulverizer, and optionally a fibrous substance,
It is also possible to employ a method in which a powdery or fibrous and, if necessary, a liquid resin is thoroughly mixed by a mixer, and then the obtained mixture is subjected to a fleece making machine to form a mat-like fleece.

Next, the face material 3, the precursor in the uncured state, and the face material 2 are sequentially arranged in a metal frame or the like set so as to be molded to have a desired thickness and specific gravity, and then hot pressed by a press. The three-layer structure can be manufactured by molding and curing the precursor to form the cured body 1, and at the same time, the cured body 1 and the face materials 2 and 3 are integrally bonded. Here, the form of the thermosetting resin is generally in accordance with a method for producing an uncured molded body (hereinafter referred to as a precursor) that can be converted to a waste paper cured body by heat curing, for example, a dry method or a wet method. Is used in combination with a powdery and / or fibrous solid resin, and if necessary, a liquid resin. Among them, the fibrous resin is not accompanied by the generation of dust like the powdered resin generally used in the dry method, and also in the wet method typified by the wet papermaking method, rather than the powdered resin, It is particularly preferable in that it is hard to coagulate in water, easily disperses, forms a uniform dispersed state with the waste paper, and does not easily cause clogging or leakage in the papermaking rope.

When the resin is formed into a fibrous shape, generally, from the viewpoint of stability and easiness, generally, it is originally 5
A water-containing or non-water-containing resin having a melting point of 0 ° C. or higher is selected, and can be fiberized by a conventional melt spinning method, for example, a nozzle method, a rotating roll method, a flash method, etc., but preferably, Melt spinning method using centrifugal force, that is, heated and rotating at high speed,
This is a spinning method in which a resin is put into a cylindrical disk having a through hole or a slit on its outer peripheral surface, and the resin is jetted from the through hole or the slit to form a fiber.

Thus, the multilayer structure of the present invention comprises at least the waste paper and optionally the fibrous material added,
A precursor formed from a mixture containing a thermosetting resin, a laminate of the precursor, or both surfaces of a multilayer precursor in which a face material (for example, a nonwoven fabric, a woven fabric, etc.) is arranged between a plurality of precursors, or Place the face material in contact with one side, and heat this with ventilation.
A multilayer structure composed of a surface material and a cured material by heat treatment by oven heating or the like, or by heating and pressurizing with a pressing machine, a pultrusion molding machine, an extruder or the like to cure the precursor and integrate it with the surface material. Plates (flat plates, corrugated plates, etc.)
Not only that, it must be manufactured by molding a long object with a curved surface (for example, an arc, hollow or solid cylinder, prism, etc.) and, if necessary, adhering an appropriate soft surface finish to the surface material with an adhesive. You can When manufacturing the multilayer structure, either a batch method or a continuous method may be adopted.

In this case, since the thermosetting resin contained in the precursor also functions as an adhesive for the surface material during molding, it is not necessary to apply the adhesive to the surface material.
In order to increase the adhesive strength, a surface material, or in some cases, the surface of the precursor may be coated with a primer or an adhesive, if necessary, and a film or sheet having an adhesive function may be arranged. In addition, the cured body that forms part of the multilayer structure is
If the molding operation as described above is adopted, the specific gravity can be adjusted to 1 or less, and thus it is possible to contribute to the weight reduction and the cost reduction of the multilayer structure as a whole.

The multilayer structure of the present invention can also be manufactured by integrally bonding a cured product obtained by molding and thermosetting in the same manner as described above and a surface material with an adhesive. The adhesive used is arbitrarily selected according to the purpose, but specifically, a phenol resin,
Examples include curable adhesives such as urea resins, melamine resins, urethane resins and epoxy resins, and adhesive adhesives such as vinyl acetate resins, hot melt resins and elastomers.

In the production of the cured product, if necessary, for example, a filler such as a lightweight aggregate or a solid aggregate, a flame retardant, a plasticizer, an insect repellent / bactericide, a pigment or the like may be used. You can also The multi-layer structure of the present invention thus obtained is low in cost and light in weight, and has practically unobstructed strength, workability such as saw workability and nailability, so that it can be used as a wood substitute material. It can be used in the fields of materials for construction, civil engineering, packaging, and transportation.

[0022]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Reference Example (Production Example of Fibrous Novolac Phenolic Resin) In a cylindrical disk rotating at high speed (rotation speed 8000 rpm) and provided with a wire mesh of 20 mesh on the outer periphery, 15
While blowing hot air of 0 ° C., a novolac-type phenol resin that has been heated and melted is added to obtain a fibrous resin,
Next, this was subjected to a crusher equipped with a large number of pins to produce a fibrous novolac type phenol resin having an average diameter of 12 μm and an average length of 2 mm.

Example 1 10 liters of water and 20 newspapers in a Henschel mixer
Waste paper slurry obtained by stirring for 120 seconds after adding 0 g, 200 g of fibrous novolac type phenol resin produced in Reference Example, and 350 g of hexamethylenetetramine
After putting and into the mixing tank, stirrer (rotation speed 60
A mixture was prepared by stirring at 0 rpm for 20 minutes. Then, after putting the mixture into a standard square sheet machine manufactured by Toyo Seiki (papermaking mesh 100 mesh, 250 × 200 mm), water is discharged from the bottom surface and further squeezed and dehydrated to obtain a water content of 20.
A 0% wet state precursor was made into paper. Then, the wet precursor was dried in an oven at 80 ° C. to prepare an uncured precursor having a thickness of 18 mm and a specific gravity of 0.45.

Next, a urea resin adhesive (trade name, Euroid 120, manufactured by Mitsui Toatsu Kogyo Co., Ltd.) was applied in advance in a metal frame having a height of 18 mm, and a plywood having a thickness of 2 mm, the above-mentioned uncured precursor And 2 mm thick plywood similar to the precursor are placed one after another and pressure 1
After heat and pressure molding under the molding conditions of 0 kg / cm ² , temperature of 160 ° C. and time of 30 minutes, it was taken out, cooled, and the peripheral part was cut to obtain a 240 mm × 190 mm × 18 mm three-layer structure. . About the obtained three-layer structure, specific gravity and three-point bending test method (test piece 120 mm × 30 mm × 18 mm, span 80
(mm) bending strength was measured. In addition, as a result of observing the sawing workability, nailing property and deformation resistance, surprisingly, it is easier to cut and does not have a chip on the side, and has excellent sawing workability, as compared with the one without a face material, Even in the test (using screw nails, the depth is 20 mm), the nails are extremely easy to pass through and there is no loss of the hardened paper due to chipping or cracking, and the holding power of the nails is 35 kgf on the side surface of the hardened material and on the surface material. From 67kgf, it was practical. Moreover, no warpage was observed even when left at room temperature, and it had excellent deformation resistance. The results are shown in Table 1.

Example 2 Example 1 was repeated except that 160 g of waste newspaper was charged into the Henschel mixer and 40 g of glass fiber having a length of 6 mm and an average diameter of 9 μm was further charged into the mixing tank. 240mm × 190mm
A three-layer structure having a size of 18 mm was obtained. Next, with respect to the obtained three-layer structure, the specific gravity and bending strength were measured in the same manner as in Example 1, and the sawing workability, nailing property and deformation resistance were observed, and as a result, the same as in Example 1. It is extremely easy to cut and exhibits excellent sawing workability without the occurrence of chipping on the sides. It is extremely easy for nails to pass through in a nailing test, and there is no loss of the hardened paper part due to chipping or cracking. 40kg on the side
f and 75 kgf from the surface material was practical. Moreover, no warpage was observed even when left at room temperature, and it had excellent deformation resistance. The results are shown in Table 1.

[Table 1] Example 1 Example 2 Specific gravity 0.56 0.56 Bending strength (kgf / cm ² ) 250 320 Good nailability Good retention of nails (side of cured body of waste paper) 35 40 ( kgf) (on surface material) 67 75 Saw workability Good Good Deformation resistance None None

[0028]

As described above, according to the present invention, one layer of a cured waste paper obtained by curing and binding a waste paper and a fibrous substance optionally added thereto with a thermosetting resin is present, and an appropriate surface material is provided. Since it is a combined multi-layer structure, it has the following features. (1) It is a low cost and light weight material, and has strength that does not hinder practical use, sawability, workability such as nailability and nail holding power, and deformation resistance. Can be used. (2) Since waste paper that has been conventionally disposed of can be recycled and a thin surface material can be used, it can contribute to the conservation and protection of wood resources.

[Brief description of drawings]

FIG. 1 is a perspective view of a plate-shaped three-layer structure showing one embodiment of the multilayer structure of the present invention.

FIG. 2 is a perspective view of a plate-shaped five-layer structure showing one embodiment of the multilayer structure of the present invention.

[Explanation of symbols]

 1,5,6 ... Waste paper cured body 2,3,7,8,9 ... Face material

Claims (6)

[Claims] 1. An aggregate having an arbitrary combination of a hardened layer and a face material layer obtained by curing a mixture containing crushed or defibrated waste paper and a thermosetting resin, and the outermost layer. At least one surface is a face material layer. 2. The multilayer structure according to claim 1, wherein the mixture further contains a fibrous material other than waste paper-derived fibers. 3. A structure having an arbitrary combination of a layer formed from a mixture containing pulverized or defibrated waste paper and a thermosetting resin and a face material layer, and at least one surface of the outermost layer is a surface. A method for producing a multilayer structure, comprising: a step of forming an aggregate, which is a material layer; and heating and pressurizing or heating and curing-bonding the aggregate obtained in the step. 4. The method for producing a multilayer structure according to claim 3, wherein the thermosetting resin has a fibrous shape. 5. A layer formed from a mixture containing pulverized or defibrated waste paper and a thermosetting resin is heat-pressed or heated and cured to obtain a cured layer and a face material layer in any combination. A method for producing a multi-layer structure having a structure, wherein at least one surface of the outermost layer is a face material layer, and the respective layers of the integrated body are integrated by an adhesive. 6. The method for producing a multilayer structure according to claim 3, wherein the mixture further contains a fibrous substance other than waste paper fibers.