JPH10138353A - Plate or molded product and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a plate or a molded product jointly equipped with excellent moisture permeability and hish strength by a method wherein the plate product or molded product is composed of a mixed fiber of only vegetable fiber or vegetable fiber and another organic and/or inorganic fiber, and an isocyanate curable composition of joining those fibers together, and molded by compression. SOLUTION: A plate product or a molded product is manufactured by forming and compression molding with a sheet shaped material composed of mixed fiber of only palm fiber or palm fiber and another organic and/or inorganic fiber, knitted textile composed of vegetable natural fiber arranged on at least one surface of the fiber layer and/or inside that, nonwoven fabric or bamboo fiber, etc., and isocyanate curable resin joining those fibers together. The palm fiber herein is fiber bark, petiole base fiber, masocarp fiber, etc., which are sampled from palm family plant such as cocopalm or the like. Hemp fiber or the like is used as the organic fiber, polyester fiber or the like is used as the synthetic resin, and glass fiber or the like is used as the inorganic fiber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate-like body similar to a wood fiberboard and a molded body obtained by molding the same into a predetermined shape, and particularly to a plate-like body exhibiting excellent performance in both moisture permeability and strength. Body or molded body.

[0002]

2. Description of the Related Art Conventionally, when a fiber-based heat insulating layer such as glass wool is formed in a wall of a wooden house, a ventilation layer is formed between the outer wall and the heat insulating layer in order to release water vapor in the room to the outside. Then, the water vapor in the room, which has passed through the heat insulating layer, diffuses from under the eaves to the outside through the ventilation layer. In that case, a windproof layer that separates the ventilation layer and the heat insulating layer is required. The windproof layer has a function of retaining the heat insulating layer, but must have excellent moisture permeability so that water vapor can be easily transmitted to the ventilation layer.

[0003] Conventionally, as a material for forming the windproof layer,
For example, polyethylene non-woven fabric has been used, but if glass wool or the like is used for the heat-insulating layer, the non-woven fabric swells and deforms due to the expansion force of the heat-insulating layer, narrowing and sometimes closing the ventilation layer. This is particularly likely to occur when a large amount of glass wool or the like is packed in a cold region (see the standard specifications for construction work, JASS24 insulation work (edited by the Architectural Institute of Japan)). Therefore, among the fiberboards, a sheathing board, which is a kind of a soft fiberboard having relatively small density and air permeability, is applied to the outside of the heat insulating layer, and the end side thereof is a structure such as a pillar, a stud, a beam, a girder or a brace. By fixing to a material, a windproof layer having a certain strength is formed.

[0004]

However, the above-mentioned conventional sizing board cannot withstand the expansion force of the heat insulating layer, but does not have such strength as to function as a structural face material. Therefore, the strength of the structural portion around the seasing board had to rely exclusively on the above-mentioned structural material other than the seasing board.

[0005] In the conventional production of plywood and the like, formalin-based resins such as urea resins and phenolic resins have been used in many cases. This is a major problem for airtight houses. The present invention has been made in view of such a point, and the first problem is, assuming the use of vegetable natural fibers that have a higher bond strength with resin than artificial fibers, Among them, coconut fibers where large gaps are formed between the thick fibers are collected and the fibers are securely fixed to each other with resin, while vegetable fibers such as hemp fibers having appropriate tensile strength and tensile elasticity To provide a plate-like body or a molded body having both excellent moisture permeability and high strength by integrating and reinforcing a sheet-like material made of a flake such as a knitted woven fabric, a nonwoven fabric, or a bamboo made of a natural fiber with a resin. It is in.

A second object of the present invention is to provide a plate-like body or a molded body which uses an isocyanate-based resin for fixing the fibers to each other, thereby greatly reducing the amount of formaldehyde emitted. . Further, the present invention also proposes a manufacturing method thereof.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have reached the following invention.
That is, the present invention provides: [1] Compression molding comprising a plant fiber alone or a mixed fiber of a plant fiber and another organic and / or inorganic fiber, and an isocyanate-based curable composition binding the fiber. And a molded article obtained by [2] At least one surface and / or inside of a layer of vegetable fibers alone or a mixed fiber of vegetable fibers and other organic and / or inorganic fibers is made of a flake, such as a knitted woven fabric, nonwoven fabric, or bamboo fiber made of vegetable natural fibers. The present invention relates to the plate-like body and the molded body according to the above [1], wherein the sheet-like objects are arranged. [3] The above-mentioned [1] and [2], wherein the plant fiber is a coconut fiber.
The present invention relates to the plate-like body and the molded body described in the above. [4] The plate-like body and the molded article according to the above [1] and [2], wherein the plant fiber is an oil palm fiber. [5] The plate-like body and the molded article according to the above [2] to [4], wherein the vegetable natural fiber is hemp. [6] The isocyanate-based curable composition has a carbon number of 8 to
The present invention relates to the plate-like body and the molded body according to the above [1] to [5], which are a composition containing a metal salt of an aliphatic carboxylic acid having 28 and an organic polyisocyanate compound as essential components. [7] The isocyanate-based curable composition has a carbon number of 8 to
A plate-like composition according to any one of the above [1] to [5], wherein the composition is an aqueous composition emulsified by an emulsifier, comprising a metal salt of an aliphatic carboxylic acid having 28, an organic polyisocyanate compound and an emulsifier as essential components. And a molded article. [8] The above-mentioned [6], wherein the organic polyisocyanate compound is polymethylene polyphenyl polyisocyanate;
[7] A plate-like body and a molded body according to [7]. [9] A fiber mat formed from defibrated plant fibers alone or a mixed fiber of plant fibers and other fibers, and if necessary, at least on one surface and / or inside the fiber mat, a sheet-like sheet made of vegetable natural fibers The present invention relates to a method for producing a plate-like body and a molded body according to the above [1] to [8], which are obtained by arranging articles, attaching an isocyanate-based curable composition to them, and compressing and molding.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The plate-like body or the molded body of the present invention comprises a palm fiber alone or a mixed fiber of palm fiber and other organic and / or inorganic fibers, and at least one surface and / or inside a fiber layer thereof. It is made of a knitted woven fabric, a nonwoven fabric, or a sheet made of flakes such as bamboo fibers, and an isocyanate-based resin binding the fibers, and is obtained by compression molding. Demonstrates excellent performance in both moisture and strength.

The coconut fibers used in the present invention include coconut palm, oil palm, sago palm, date palm, sardine palm, nipa palm, sugar palm, pea palm, palm, tojuro, black clog, etc., fibrous bark and petiole. Fibers such as base fiber and mesocarp fiber, which include fibers obtained by defibrating empty fruit clusters of oil palm.
Also, a mixture of a plurality of types of coconut fibers is included.

[0010] Palm fibers are as thick as about 100 to 600 µm in diameter. Therefore, when a fiber mat is formed, depending on the fiber packing density, the size between the fibers is, for example, about 100 µm to 5 mm, preferably about 200 µm to 3 mm. A gap is formed. Therefore, the moisture permeability of the fiber mat is extremely good. Depending on the amount of resin or the degree of compression during molding when the isocyanate-based resin is adhered to the fiber mat and compression-molded, the size of the gaps and the density of the gaps between the fibers of the obtained plate-like body or molded body are variously changed. Can be changed. This makes it possible to control the moisture permeability of the plate or the molded body.
For example, by setting the gap between the plate-like body or the formed body to about 1 to 100 μm, usually about 5 to 50 μm, it is possible to produce a good plate-shaped body or a formed body having air permeability but not allowing rain to pass. is there.

Further, the palm fiber has a diameter of about 100 to 6
Since it is as thick as 00 μm, long, about 5 to 30 cm in length, bent, and has a large entanglement between fibers, the plate-like body or the molded body has excellent nail holding force when nailed. It is preferable to use oil palm fiber as the palm fiber. This oil palm fiber is obtained by defibrating empty fruit clusters of oil palm. Oil palm fiber requires less labor for defibration and the like than other types of palm fiber, so that the energy required for production can be saved and the cost is low. For example, coconut fibers require a large amount of energy for a long period of time to be mechanically fibrillated after being immersed in water for a long time to soften the coconut shell. On the other hand, in the case of oil palm, since empty fruit clusters which are originally aggregated in a fibrous state are fibrillated, there is no need for immersion in water, and the energy required for fibrillation is extremely small. In addition, oil palm fiber is preferable because it has less dusting property than coco fiber and can avoid deterioration of working environment in handling.

The oil palm fiber is optionally washed before and after defibration to remove oil and odor. The oil palm fiber alone has a high rigidity and a cross-sectional diameter of 100 to 6
It is about 00 μm and its hair foot, that is, the length is about 5
It is about 30 cm, and by defibrating the fiber, a high degree of entanglement can be expected. In addition, oil palm oil can be used to extract oil palm oil, but the empty fruit bunch remaining after harvesting this fruit has no specific use at present and is usually destined to be discarded. It has the advantage of being available at

Further, the fiber mat may be mixed with organic or inorganic fibers as required. Organic fibers include natural vegetable fibers and synthetic fibers. Here, the natural vegetable fiber is hemp fiber which is fibrillated hemp, bamboo fiber which is fibrillated young bamboo, sugarcane fiber, hechima fiber, pineapple fiber,
Examples include banana fiber, koulyang fiber, fiber obtained from Inawara, and wood fiber, and there is no particular limitation as long as the fiber is obtained from a natural plant. As synthetic fibers, polyester fibers, aliphatic or aromatic polyamide fibers, aramid fibers, polyolefin fibers such as acrylic fibers, polyethylene fibers, polypropylene fibers, vinylidene fibers, polyvinyl chloride fibers, polyurethane fibers, vinylon, rayon, cupra, acetate, etc. Are exemplified. Examples of the inorganic fiber include asbestos, glass fiber, carbon fiber, boron fiber, silicon nitride fiber, silicon carbide fiber, and Tyranno fiber. These may be mixed alone or in combination of two or more.

When vegetable natural fibers such as hemp fiber and bamboo fiber are mixed with the fiber mat, the diameter of the palm fiber is about 1
Since the diameter of the hemp fiber is about 5 to 30 μm and the diameter of the bamboo fiber is 10 to 200 μm, the natural vegetable fiber such as the hemp fiber and the bamboo fiber crosses the palm fiber at the intersection of the palm fiber. It is considered that the entanglement of the palm fibers increases the bonding strength between the palm fibers.

In order to form a fiber mat, the peel strength is increased by entanglement of the coconut fiber into a non-woven fabric or a three-dimensional knitted structure by a needle punch or the like, and further, if necessary, by pressing or hot pressing. Make the mat denser. The thickness of the fiber mat is usually 5 mm to 2 mm.
It is said that it is easy to use when the thickness is about 0 mm, but it is needless to say that the present invention is not limited to this and may be arbitrarily set according to the application. Furthermore, the basis weight of this fiber mat is, for example, 0.5 k
g / m ² ~6kg / m ² can be mentioned. The fiber mat may be used by stacking a plurality of fiber mats depending on the application.

[0016] The knitted fabric includes, for example, a cloth obtained by knitting hemp yarn obtained by fibrillating hemp fibers in a vertical and horizontal direction, and thus includes a jute cloth which is a cloth formed of jute. In addition, as for the nonwoven fabric, a hemp fiber obtained by defibrating hemp is made into a web in a dry manner, hardened with an adhesive such as a latex of natural rubber, dried and finished, and formed into a nonwoven fabric and a thin nonwoven fabric formed by a wet papermaking method. And paper formed by fibrillating wood fibers and wet papermaking. In addition, the sheet-like material includes a material obtained by knitting a thin strip-like thin piece cut out of a bamboo material or the like vertically and horizontally (actually, it is close to a weave). These knitted and woven fabrics, nonwoven fabrics and sheet materials have air permeability and are excellent in moisture permeability. Vegetable natural fibers used in knitted fabrics, nonwoven fabrics and sheets may be a mixture of a plurality of types of vegetable natural fibers. Further, two or more kinds of knitted fabrics, nonwoven fabrics and sheet materials may be used.

The knitted fabric or sheet-like material is knitted or woven with hemp fibers or bamboo flakes having a high tensile strength and tensile elasticity, and therefore exhibits excellent tensile strength and tensile elasticity itself. The nonwoven fabric has a lower strength than a knitted fabric such as hemp or a sheet material such as bamboo. Therefore, a knitted fabric or a sheet material is preferable, but it has a function as a resin holding material. If necessary, synthetic fibers such as nylon, polypropylene, polyethylene and polyester may be mixed with the natural fibers forming the nonwoven fabric.

Since the knitted fabric, nonwoven fabric or sheet is strongly bonded to the fiber mat via the resin, the strength of the plate or the molded body is increased. That is, when a knitted fabric, a nonwoven fabric, or a sheet is placed on the surface of the fiber mat, particularly on both surfaces, a so-called sandwich effect is exhibited, and the bending strength and the flexural modulus of the plate or formed body are increased. On the other hand, when the knitted fabric, nonwoven fabric or sheet is placed inside the fiber mat, the tensile strength and tensile modulus, shear strength and shear modulus, and in-plane compressive strength and The inner compression modulus increases. This in-plane compressive strength means the strength when receiving a compressive force in a plane stress state. Further, the knitted fabric or sheet-like material absorbs water,
Since the dimensional change at the time of moisture absorption is small, when it is arranged on the surface or inside of the fiber mat, the dimensional change at the time of water absorption and moisture absorption of the plate-like body or the molded body is small, and the strength decrease at the time of water absorption and moisture absorption is small.

Further, this knitted fabric, the basis weight of the nonwoven fabric or sheet is 10g / m ² ~1500g / m ^2, the strength and moisture permeability, preferably from the viewpoint of shape stability. More preferably 100g / m2~600g / m ^2, more preferably 1
It is a ^{50g / m 2 ~350g / m 2} . The basis weight is 10 g / m
^In the case of ² or less, the reinforcing effect such as the bending strength and the compressive strength described above becomes small. Further, when the basis weight is 1500 g / m ² or more, a knitted woven fabric, a nonwoven fabric, a sheet-like material is deformed into a plate-like body,
The molded article is dragged, resulting in increased warpage and twist after molding.

In the present invention, a knitted fabric using hemp fiber is particularly preferable. Here, the hemp includes those that take the skin fibers such as hemp (burlap), hemp, flax, mao, and ambassadors, and those that take the tissue fibers such as Manila, sisal, New Zealand and Mauricias. Hemp fibers refer to fibers obtained from these hemp. The fiber of hemp (burlap) is called jute, and hemp fiber here includes jute.

Examples of hemp knitted and woven structures include plain weave,
It is preferable to select from twill weave, satin weave, nanako weave (including regular and irregular), and among them, plain weave and twill weave are particularly preferred. The knitting structure is selected from flat knitting, rubber knitting and the like.
The driving density is selected according to the combination of the weave structure and the yarn count.
If it is necessary to further improve the water resistance of the knitted fabric, nonwoven fabric or sheet, a water repellent such as silicone may be applied to the surface of the knitted fabric or sheet. Further, a flame retardant, a coloring agent, a preservative, an ant-inhibiting agent, a fungicide, or the like may be applied to the palm fiber, the knitted fabric, the nonwoven fabric, or the sheet-like material as required.

The metal salt of an aliphatic carboxylic acid having 8 to 28 carbon atoms used in the present invention includes octylic acid, lauric acid, myristic acid, palmitic acid, stearic acid,
Examples thereof include zinc, iron, aluminum, calcium, zirconium, magnesium and barium salts of aliphatic carboxylic acids such as oleic acid and behenic acid. As the aliphatic carboxylic acid, any of mono, di and tri functional groups can be used, and among them, a linear aliphatic monocarboxylic acid having 12 to 22 carbon atoms is preferable.

The organic polyisocyanate compound used in the present invention is an isocyanate compound or isocyanate polymer, for example, tolylene diisocyanate (TD
I), 4,4'-diphenylmethane isocyanate (MD
I), hexamethylene diisocyanate (HMDI), xylene diisocyanate (XDI), isophorone diisocyanate (IPDI), polymethylene polyphenyl polyisocyanate (polymeric MDI) and the like. Among these, polymeric MDI is particularly preferred.

The emulsifier used in the present invention may be a commonly used emulsifier, such as fatty acid soap, rosin acid soap, alkyl sulfonate, alkylbenzene sulfonate, dialkylaryl sulfonate, alkyl sulfosuccinate. , Polyoxyethylene alkyl sulfate, anionic surfactant such as polyoxyethylene alkyl aryl sulfate, polyoxyethylene alkyl ether,
Examples of the surfactant include polyoxyethylene alkylaryl ether, polyoxyethylene sorbitan fatty acid ester, and oxyethylene oxypropylene block copolymer. These surfactants may be used alone or in combination of two or more. Since the curable composition used in the present invention is emulsified by an emulsifier and can be emulsified in water, the viscosity can be easily adjusted by diluting the composition with water. The isocyanate-based curable composition obtained by mixing and emulsifying the above components is in an aqueous solution or aqueous dispersion state before curing, and in this state,
Attached to fiber mats and knits, nonwovens, or sheets. By being in an aqueous solution or dispersion state,
The affinity and the permeability to the natural fiber surface are improved, and an effective film can be formed on the fiber surface with respect to the adhesiveness and water resistance.

Further, the concentration of the resin component in the aqueous solution or dispersion of the resin before curing is preferably from 70% by weight to 15% by weight, more preferably from 65% by weight to 20% by weight. When the concentration is 70% by weight or more, the viscosity is usually too high, and the resin is difficult to spread evenly on the natural fiber surface, the effective film formation is insufficient, the adhesion between the fibers is insufficient, and the The adhesion operation becomes difficult. When the concentration is 15 wt% or less, a large amount of water is simultaneously attached to the natural fiber together with the resin, and during the hot pressing, the heat is taken away by the latent heat of evaporation of the water, the adhesive strength is reduced, and the strength and strength of the molded body are reduced. The strength in the wet state is reduced, and the effect of dilution with water is reduced. Further, it is not preferable because a large amount of energy is required for drying after the adhesion.

The viscosity at 25 ° C. of the aqueous resin solution or aqueous dispersion before curing is preferably 0.02 to 100 poise, more preferably 0.05 to 10 poise. 25
If the viscosity at 100 ° C is 100 poise or more, the fluidity is insufficient, the resin is difficult to spread evenly on the natural fiber surface, the effective film formation is insufficient, the adhesion between the fibers is insufficient, and It is difficult to perform the adhesion operation, and the adhesion state becomes uneven. On the other hand, when the viscosity is less than 0.02 poise, the fluidity is too high, and when the resin is adhered to the fiber mat, the resin liquid flows and the adhesion efficiency is reduced.

Since the amount of the resin used depends on the physical properties required for the plate-like body, it cannot be specified unconditionally. For example, 5 parts per 100 parts by weight of the fiber including the fiber mat and the hemp cloth are used.
To 100 parts by weight, preferably 5 to 50 parts by weight, more preferably 10 to 30 parts by weight. Further, the strength of the plate-like body can be changed by changing the amount of the resin used for the hemp cloth. That is, as the amount of resin used for the hemp cloth increases, the strength of the plate-like body can be increased. For example, the amount of resin used for hemp cloth is 5 to 500 parts by weight, preferably 5 to 150 parts by weight, per 100 parts by weight of hemp cloth.
Parts by weight are exemplified. When the amount of the resin is less than 5 parts by weight, the laminating effect of the hemp cloth is hardly exhibited, and when the amount is 500 parts by weight or more, the effect of increasing the amount is hardly obtained.

The isocyanate-based curable composition of the present invention may contain, if necessary, a plasticizer, a filler, a reinforcing material, an anti-sagging agent, a coloring agent, an antioxidant, an adhesion promoter, a curing catalyst, and physical property adjustment. An agent may be blended. In addition, as an adhesion imparting agent,
Konjac, flour, starch and the like may be added. The method for attaching the isocyanate-based curable composition to palm fiber or the like is not particularly limited. Since a large gap is formed between the fibers in the fiber mat of the coconut fiber, when the resin is supplied by spraying or dipping, the resin uniformly adheres to all the fibers via the gap, and the plate-like body or the molded body is formed. The intensity distribution becomes narrow.

The thickness of the plate of the present invention is preferably 3 to 25 mm, more preferably 9 to 20 mm. If the thickness of the plate is 3 mm or less, sufficient bending strength cannot be obtained,
If the thickness is 5 mm or more, it is conceivable that the wall thickness may be increased in use, which is not practical in use. The density of the plate is 0.
It is preferably from 2 to 1.0 g / cm ³ , and more preferably from 0.3 to 0.1 g / cm ³ .
7 g / cm ³ is preferred, and most preferably 0.35 to
0.6 g / cm ³ . The basis weight of the plate-shaped body is, for example, when the thickness of the plate-shaped body is 9 mm, the density is 0.2 g / cm ^3.
In basis weight 1.8 kg / m ^2, and the density is 1 kg / m ³ in basis weight 9 kg / m ^2. When the density is 0.2 g / cm ³ or less, the strength of the plate-like body is not sufficient. When the density is 1 g / cm ³ or more, the moisture permeability decreases, and the weight of the plate-like body or the molded body increases, so that the handling becomes poor.

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a plate-like body 1 according to a first embodiment. The plate-like body 1 is formed by adhering a resin to a fiber mat 2 made of palm fiber mixed with vegetable natural fibers such as hemp fiber and bamboo fiber as needed, and compression molding. FIG. 2 shows a plate-like body 3 according to a second embodiment. On both surfaces of a fiber mat 2, hemp cloths 4 made by weaving yarns made of hemp fibers vertically and horizontally are arranged as knitted fabrics, and resin is applied to these. It is a plate-like body 2 which is adhered and formed by compression molding.

The production method of the above-mentioned plate-like bodies 1 and 3 is as follows. First, coconut fibers and, if necessary, hemp fibers are defibrated to produce fibers having a unit cross-sectional diameter of about 5 to 600 μm and a length of about 5 to 30 cm. obtain. The defibrated coconut fibers include fibers having a larger cross-sectional diameter, thinner fibers, longer fibers and shorter fibers, but can be used as they are. At this time, since the natural length of the coconut fiber is about 5 to 30 cm, there is no particular need to process it. Next, the fibrous mat 2 is formed by mixing the fibrillated palm fiber with the fibrous natural fiber such as hemp fiber and bamboo fiber, if necessary. The mechanism used in this step includes, for example, a plurality of first, second, etc. hoppers 12, 12,... Above a belt conveyor 11, as shown in FIG.
Are provided in series in the belt traveling direction, and the spray guns 13 are arranged so as to be directed to the vicinity of the outlet of each hopper 12, respectively.
The heating and pressing roller 14 is provided downstream of the hopper 12 with the belt conveyor 11 facing the same. Each hopper 12
, A mixed fiber obtained by mixing coconut fiber, hemp fiber, bamboo fiber, or the like at an appropriate ratio, and supplying an aqueous solution or aqueous dispersion of the resin to the spray guns 13, 13,. And
At the same time as the operation of the belt conveyor 11, the mixed fibers are dropped and supplied from each hopper 12 onto the belt conveyor 11, and
By spraying and supplying the aqueous resin solution or the aqueous dispersion from the respective spray guns 13 toward the mixed fibers, the lowermost first layer is formed on the belt conveyor 11 by the mixed fibers from the first hopper 12. Then, a second layer is formed from the mixed fibers from the second hopper 12, and a fiber layer is sequentially formed thereon. Thereafter, the fiber mat 2 is formed by press-molding with a heat-pressing roller 14. Of course, when fibers are not mixed, only coconut fibers may be supplied to all hoppers 12, or only one hopper 12 and one spray gun 13 may be used. The spray gun 13 is connected to the hopper 12
May be arranged in front of the vehicle. Also, by changing the characteristics (mixing ratio, fiber thickness, fiber length) of the fibers supplied to the first, second... Plural hoppers 12, 12,. Can be changed. Especially fiber mat 2
Thick coconut fibers are arranged at the center and thin coconut fibers are arranged on both surfaces. As a result, the contact density of the fibers on the surface side of the fiber mat 2 is increased, so that the plate-like body to be molded from this is good. Is obtained.

Next, hemp cloths 4 and 4 are arranged on both sides of the fiber mat 2, resin is adhered to these, and hot compression molding is performed. The mechanism used in this step is, for example, as shown in FIG. 3, while hemp cloths 4 and 4 are continuously supplied from above and below while pulling the fiber mat 2 forward, and spray guns 13 are respectively arranged at the merging portions. , And heat-pressing rollers 15, 15 are provided opposite to each other downstream thereof. An aqueous resin solution or aqueous dispersion is supplied under pressure to the spray guns 13, 13,.... At the same time as the operation of the belt conveyor 15, an aqueous resin solution or an aqueous dispersion is sprayed and supplied from each spray gun 13.
The plate-shaped body is continuously formed by heating and pressing at 5 and 15.

In addition to the continuous molding method, there is also a method of molding one sheet at a time. In this case, a resin is attached to the fiber mat 2 to form a mold, and hemp cloths 4 and 4 are attached to the fiber mat 2 via a resin, followed by thermocompression molding using a hot press or the like. Further, the plate-like bodies 1 and 3 are arranged as follows.
You may shape | mold each sheet. The resin is added to the natural vegetable fiber and stirred to allow the resin to adhere.

Next, a hemp cloth 4 coated with a resin is laid on the bottom of a mold (not shown), the above fibers are filled from above, and finally the hemp cloth 4 is laid. This is molded with a predetermined thickness and a predetermined density by a hot press or the like to obtain a plate-like material. Moreover, in the said embodiment, when molding the fiber mat 2, the case where the defibrated vegetable natural fiber is directly filled in the mold has been described. However, the fiber is woven into the cloth and the resin is applied to the cloth. It may be impregnated, laminated in multiple layers, and molded. Thereby, a large physical strength can be obtained without impairing the moisture permeability.

Although the resin is attached to the fibers by spraying with a spray gun 13 or the like, the resin may be attached by immersing the fibers in the resin. The resin is used as a sizing agent or a binder for the fiber mat 2, and imparts strength to the hemp cloth itself and a binder between the hemp cloth 4 and the fiber mat 2, and also a binder or strength for the entire plate-like body. Serves as a constitutive agent for application.

Accordingly, in the plate-like body 3 of the second embodiment, the fiber mat 2 is a palm fiber mixed with vegetable natural fibers such as hemp fiber and bamboo fiber, and the hemp cloth 4 is formed of hemp fiber. Since the irregularities on the surface are larger than those of the artificial fibers and the like, the entanglement strength between the fibers is higher than that of the artificial fibers, and the bonding strength with the resin by the so-called anchor effect is excellent. Moreover, the diameter of the palm fiber is about 100 to 6
For example, hemp fiber has a diameter of about 5 μm.
Since it is as thin as ~ 30 [mu] m, vegetable natural fibers such as hemp fibers are entangled at intersections of palm fibers and the like, and the bonding strength between palm fibers is increased. In addition, bamboo fiber etc. is a flat shape,
Due to its rigidity, mixing with palm fiber has the meaning of improving strength. Therefore, if the windproof layer is formed by this plate-like body, the heat insulating layer can be stably held with high strength, and the plate-like body can reinforce the structural portion around the windproof layer.

The palm fiber has a diameter of about 100 to 60.
Since it is as thick as 0 μm, when the fiber mat 2 is used, for example, 100 μm to 5 m
Since a gap having a size of about m is formed, the moisture permeability of the fiber mat 2 is extremely good. The hemp cloth 4 also has excellent breathability because the stitches have air permeability. Therefore, the plate-shaped body of the present invention obtained from these materials has various strengths and moisture permeability depending on the amount of the resin, the amount of the fiber mat 2 and the amount of the hemp cloth 4 and the compression ratio at the time of compression molding. be able to. Therefore, this plate-like body functions as an excellent windbreak layer.

In the above embodiment, the fiber mat 2 is formed by mixing vegetable fiber such as hemp fiber and bamboo fiber with palm fiber as necessary. However, the fiber mat 2 is formed only by palm fiber. May be. In addition, the hemp cloth 4 is knitted with hemp fiber or the like having a moderately high tensile strength and tensile elastic modulus, and therefore exhibits excellent tensile strength and tensile elastic modulus itself. The hemp cloth 4 is strongly bonded to the fiber mat 2 via the resin, so that the strength of the plate-like body is increased. That is, when the hemp cloth 4 is arranged on both surfaces of the fiber mat 2, a so-called sandwich effect is exhibited, and the bending strength and the bending elastic modulus of the plate-like body are increased. further,
Hemp cloth 4 has a small dimensional change during water absorption and moisture absorption.
In particular, it is preferable to arrange the fiber mat 2 on both sides because the dimensional change of the plate-like body or the molded body during water absorption and moisture absorption and the decrease in strength during water absorption and moisture absorption are small. Therefore, the plate-like body 3 functions as a structural surface material, and can reinforce the structural portion around the windbreak layer.

Although the knitted fabric, nonwoven fabric or sheet material 4 is arranged on both surfaces of the fiber mat 2, the present invention arranges the knitted fabric, nonwoven fabric or sheet material 4 on only one surface of the fiber mat 2. , A knitted woven fabric, a nonwoven fabric or a sheet-like material 4 arranged inside the fiber mat 2, a knitted woven fabric, a nonwoven fabric or a sheet-like material 4 arranged on both surfaces or one surface of the fiber mat 2 and the inside thereof. It is a thing.

Further, a knitted fabric, a nonwoven fabric or a sheet-like material 4
When the woven fabric, the nonwoven fabric or the sheet-like material 4 is arranged in a plurality of sheets, the knitted woven fabric, the nonwoven fabric or the sheet-like material 4 and the coconut fiber of the fiber mat 2 are alternately superposed on each other. Includes those arranged in layers. Further, when the knitted fabric, nonwoven fabric or sheet-like material 4 is arranged inside the fiber mat 2, if a treatment such as needle punching is performed in such a state, the fiber mat 2 and the knitted fabric, nonwoven fabric or The fibers of the sheet-like material 4 are well entangled with each other, so that the peel strength of the plate-like body or the molded body is increased, and the bending strength and the bending elastic modulus are improved.

When the knitted woven fabric, nonwoven fabric or sheet-like material 4 is arranged inside the fiber mat 2, the tensile strength and tensile modulus, shear strength and shear modulus, and in-plane compressive strength and Since the internal compression modulus is increased, the plate-like body functions as a structural face material, and can reinforce the structural portion around the windbreak layer. Further, in the second embodiment, only the knitted fabric 4 woven from yarn obtained from hemp fiber is used. However, a knitted woven fabric, a nonwoven fabric or a sheet, such as a combination with a sheet material 4 woven from a thin piece cut out of bamboo or the like, is used. When a plurality of articles 4 are used, they may be used in an appropriate combination.

Further, in the above embodiment, only the plate-like body having a rectangular shape in a front view and a constant thickness has been described. However, a molded body formed into a desired shape by using various shapes during compression hardening molding may be used. In this case, the same operation and effect as those of the above plate-like body can be obtained. The board of the present invention may be used as a windbreak layer used for forming a ventilation layer on the outer wall of a house as described above, but is not limited thereto. For example, home interior materials, interior base materials, roof base materials, ceiling materials, floor materials, floor base materials, tatami floors, architectural structural material heat insulating materials, sound absorbing materials, sound insulating materials, shock absorbing materials, cushioning materials, rims, etc. It can be used for all building material applications where plywood, glulam, particle board, etc. are used as building materials. Furthermore, it can also be used as a material for concrete formwork, pallets, packaging materials, interior materials for vehicles such as automobiles, interior base materials, exterior materials and the like.

[0043]

The present invention will be specifically described below with reference to examples. [Example 1] Fibers were entangled by needle punching using defibrated oil palm fibers to produce a fiber mat. Isocyanate resin UR-4000 (manufactured by Mitsui Toatsu Chemicals)
And water were mixed by a mixer to prepare an aqueous emulsion having a resin solid content of 40% by weight. An aqueous emulsion of this resin was spray-coated on both sides of the oil palm mat having a basis weight of 1.36 kg / m ^{2 by} a spray method, and 10 parts by weight of a solid content of an isocyanate resin was adhered to 100 parts by weight of coconut fiber. . Three oil palm fiber mats to which the resin was adhered were laminated and heated and pressed by a press machine at 165 ° C. for 10 minutes to obtain a 9.0 mm-thick plate.

The obtained plate was evaluated for the following evaluation items and methods.
It was evaluated by the method. Smell during molding, during press and hot plate open
Immediately after, evaluated by the odor emitted from the plate,
As shown. ○: No irritating odor, △: Irritating odor,
X: There is a noticeable pungent odor. Bending strength measurement is JIS A 5905
The measurement was performed using a fiberboard measuring method. The flexural strength test when wet is
JIS A 5905 Based on the wet flexural strength A test of fiberboard
Was. Moisture permeability is JIS Z 0208 moisture permeability test of moisture-proof packaging material
It measured according to the method. These evaluation results are shown in Table 1.
Was. [Example 2] In the same manner as in Example 1, the basis weight was 1.50 kg.
/ M^TwoCoco fiber mat, resin concentration 40 wt% iso
An aqueous emulsion of a cyanate-based resin was added to palm fiber 100
Attach so that the resin solid content is 10 parts by weight with respect to parts by weight.
I wore it. Three coconut mats are laminated and heated and pressed.
Thus, a plate having a thickness of 9 mm was obtained. The obtained plate-like body was prepared in Examples
The evaluation was performed in the same manner as in Example 1. The evaluation results are shown in Table 1. [Comparative Example 1] Urea resin U-755 (manufactured by Mitsui Toatsu Chemicals)
Is diluted with water to obtain an aqueous emulsion having a resin solid content of 40 wt%.
Was prepared. 1.30 kg per unit area in the same manner as in Example 1.
/ M ^TwoOf the urea resin prepared above
15 folds of resin solid content per 100 parts by weight of coconut fiber
It was adhered so that it became an amount. Three coconut mats
Layer and heat press at 165 ° C for 10 minutes to 9mm
A thick plate was obtained. There is a pungent odor during the heating press and the hot plate
Immediately after opening, irritating odor and gas irritating to the eyes are large from the plate.
Dissipated in quantity. The obtained plate was evaluated in the same manner as in Example 1.
The evaluation results are shown in Table 1. [Comparative Example 2] Similar to Comparative Example 1, the basis weight was 1.50 kg / m.^Two
100 parts by weight of urea resin to palm fiber mat
To 10 parts by weight of resin solids
Then, three mats are laminated and heated and pressed to 9 mm thickness.
A plate was obtained. There is a pungent odor during the heating press and the hot plate is opened
Immediately afterwards, irritating odor and gas irritating to the eyes are released from the plate.
Was. The obtained plate was evaluated in the same manner as in Example 1 and evaluated.
The results are shown in Table 1.

From the comparison between Example 1 and Comparative Example 1 in Table 1, it was found that the same physical properties as when 15 parts by weight of the urea resin were applied can be achieved with the isocyanate-based resin at a coating amount of 10 parts by weight. Further, from the comparison between Example 2 and Comparative Example 2, it was found that, even with the same coating amount, the bending strength and the wet bending strength exhibited higher physical properties when the isocyanate resin was used than when the urea resin was used. .

Further, by using an isocyanate-based resin instead of the urea resin generally used for plywood, the generation of pungent odor during production could be greatly suppressed. Example 3 An aqueous emulsion of an isocyanate-based resin having a resin concentration of 40 wt% was added to a palm fiber mat having a basis weight of 1.71 kg / m ^{2 so} that the resin solid content was 10 parts by weight based on 100 parts by weight of palm fiber. It was applied by a spray method. Then a basis weight of 0.32kg / m ² of jute cross 2
Jute cloth 1 with isocyanate resin
The resin was adhered so that the resin solid content was 10 parts by weight with respect to 00 parts by weight. Subsequently, one sheet of jute cloth, two pieces of oil palm fiber mat, and one sheet of jute cloth were laminated in this order, and heated and pressed by a press machine at 165 ° C. for 10 minutes to obtain a plate having a thickness of 9.0 mm. Was. Example 1
As a result of the evaluation, the bending strength was 15.2 N / m.
m ² , wet bending strength 5.1 N / mm ² , moisture permeability 64
g / (m ² · Hr).

[0047]

[Table 1]

[0048]

As described above, the present invention presupposes the use of vegetable natural fibers which have a higher bond strength with resin than artificial fibers, in which large gaps are formed between thick fibers. The coconut fibers are collected, and the fibers are securely fixed to each other with a resin. On the other hand, knitted fabrics, nonwoven fabrics, bamboos, and the like made of vegetable natural fibers such as hemp fibers having an appropriate tensile strength and tensile elasticity. By integrating and reinforcing a sheet-like material made of a thin piece with a resin, a plate-like body or a molded body having both excellent moisture permeability and high strength could be provided.

Further, by using an isocyanate-based curable composition for fixing the fibers to each other, the amount of formaldehyde to be diffused is greatly reduced as compared with amino resins such as urea resins generally used for plywood. A body or molded body could be provided. Furthermore, the amount of resin used to achieve the same level of strength could be reduced to a smaller amount than urea resin and the like.

Furthermore, a production method suitable for the plate-like body or the molded body of the present invention could be proposed.

[Brief description of the drawings]

FIG. 1 is a perspective view of a plate-like body according to a first embodiment.

FIG. 2 is a sectional view of a plate-like body according to a second embodiment.

FIG. 3 is an explanatory view showing a method for producing a fiber mat and a method for producing a plate-like body;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate-like body of 1st Embodiment 2 Fiber mat 3 Plate-like body of 2nd Embodiment 4 Hemp cloth (knitted fabric), nonwoven fabric, sheet-like material

Claims (9)

[Claims] 1. A plant fiber comprising a plant fiber alone or a mixed fiber of a plant fiber and another organic and / or inorganic fiber, and an isocyanate-based curable composition binding the fiber, and obtained by compression molding. Plate or molded body. 2. A woven fabric, nonwoven fabric or bamboo fiber or the like made of vegetable natural fibers on at least one surface and / or inside a layer of vegetable fibers alone or a mixed fiber of vegetable fibers and other organic and / or inorganic fibers. The plate-like body and the molded body according to claim 1, wherein a sheet-like body is arranged. 3. The plate-like body and the molded article according to claim 1, wherein the plant fiber is a coconut fiber. 4. The plate-like body and the molded body according to claim 1, wherein the plant fiber is an oil palm fiber. 5. The method according to claim 2, wherein the natural vegetable fiber is hemp.
3. The plate-like body and the molded body according to 3 or 4. 6. The composition according to claim 1, wherein the isocyanate-based curable composition comprises a metal salt of an aliphatic carboxylic acid having 8 to 28 carbon atoms and an organic polyisocyanate compound as essential components. 4. The plate-like body and the molded body according to 4, 5 or 6. 7. An aqueous composition obtained by emulsifying an isocyanate-based curable composition containing a metal salt of an aliphatic carboxylic acid having 8 to 28 carbon atoms, an organic polyisocyanate compound and an emulsifier as essential components, and emulsifying with an emulsifier. The plate-like body and the molded body according to claim 1, 2, 3, 4, 5, or 6, wherein 8. The plate-like body and the molded article according to claim 6, wherein the organic polyisocyanate compound is polymethylene polyphenyl polyisocyanate. 9. A fiber mat is formed from defibrated coconut fiber alone or a mixed fiber of coconut fiber and another fiber, and if necessary, at least one surface and / or inside of the fiber mat is made of vegetable natural fiber. The method for producing a plate-like body and a molded body according to claim 1, wherein the sheet-like body is arranged, the isocyanate-based curable composition is adhered to the sheet-like body, and compression molding is performed.