JPH1119907A - Fiberboard and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiberboard suitable for wind protection layer, which has a high strength, a favorable air permeability, a short thermocompression forming cycle and a favorable productivity. SOLUTION: This fiberboard 1 is obtained by forming a fiber mat 2 mainly made of palm fibers adhered with a composition containing an amino resin and an amino resin hardening catalyst, the pot life at 40 deg.C of which is 24 hr or longer, under heat and compression under the condition that the water content of this fiber mat 2 is set to be 40 wt.% or less of the dry weight. By that manufacturing method, the bending strength of 3-50 N/mm<2> is given to this fiberboard.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiberboard similar to a wood fiberboard and a method for producing the same, and more particularly to a fiberboard excellent in moisture permeability and strength and excellent in productivity and a method for producing the same.

[0002]

2. Description of the Related Art In a wooden house, a fiber-based heat-insulating layer such as glass wool is generally provided in a wall, and a ventilation layer is formed between the outer wall and the heat-insulating layer in order to release indoor water vapor to the outside. This allows the water vapor in the room that has passed through the heat insulating layer to diffuse from under the eaves to the outside through the ventilation layer. In that case, usually, a windproof layer is provided between the heat insulating layer and the ventilation layer in order to partition the heat insulating layer and the ventilation layer and hold the heat insulating layer. This windproof layer, besides having the function of holding the heat insulating layer, it is necessary that the water vapor that has passed through the heat insulating layer can be smoothly transmitted to the ventilation layer,
Therefore, a material having excellent strength and moisture permeability is required.

[0003] Conventionally, for example, a nonwoven fabric made of polyethylene has been used as the windproof layer. However, since the strength is insufficient, when the heat insulating layer is made of glass wool or the like, the expansion force of the heat insulating layer is pressed. As a result, there is a disadvantage that the nonwoven fabric swells and deforms to narrow the ventilation layer. This is particularly likely to occur when a large amount of glass wool or the like is packed in the heat insulating layer in a cold region (refer to JASS 24 heat insulation work (edited by the Architectural Institute of Japan)). Therefore, using a sizing board, which is a kind of soft fiberboard that has relatively low density among wood fiberboards and has air permeability, is applied to the outside of the heat insulation layer, and the edges are pillars, studs,
By fixing to a structural material such as a beam, a girder, or a brace (reinforcing material such as a torso edge, a bracing), a windproof layer having a certain strength is formed.

[0004]

However, even though the above-mentioned sizing board can withstand the expansion force of the heat insulating layer, it does not have sufficient strength to function as a structural face material. Therefore, the strength of the structural part around the seasing board had to rely exclusively on the above-mentioned structural members other than the seasing board.

Japanese Patent Application Laid-Open No. 8-336816 discloses a fiberboard having both strength and moisture permeability, in which a thermosetting resin is adhered to a fiber mat made of coconut fiber as a windproof layer, and this is thermocompression molded. Is disclosed. The thermosetting resin is usually diluted with water or the like and adhered to the fiber mat.However, if the moisture content of the fiber mat is high at the time of thermocompression molding, a long time is required for curing and the cycle of thermocompression molding is performed. And the productivity becomes poor. Since coconut fibers easily absorb moisture, this problem is particularly remarkable when producing fiber mats under humid conditions such as in Southeast Asia.

Japanese Unexamined Patent Publication (Kokai) No. 2-296004 describes that an aqueous dispersion of a curable resin is applied to an organic fiber, dried, and then molded. In this method, the moisture content of the fiber before molding is reduced, but when the curable resin is an amino resin that requires a curing catalyst, the use of a curing catalyst with a short pot life causes the amino resin to dry during drying. However, there is a problem that the fibers cannot be sufficiently bonded to each other even when compression-molded, and the strength becomes low.

The present invention is intended to solve the above-mentioned problems, and has as its object the purpose of achieving high strength, good air permeability, a short cycle of thermocompression molding, and good productivity. An object of the present invention is to provide a fiberboard suitable for a windproof layer and a method for manufacturing such a fiberboard.

[0008]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve these problems, and as a result, have used amino resins as thermosetting resins and specific ones as curing catalysts thereof. By performing thermocompression molding in a state where the moisture content of the fiber mat is set to a specific amount or less, the strength and the air permeability are higher than conventionally known fiberboards, and the cycle of thermocompression molding is short, and the production is shortened. It has been found that a fiberboard having good properties can be obtained, and the present invention has been completed.

That is, the present invention is as follows. (1) A composition containing an amino resin and an amino resin curing catalyst having a pot life at 40 ° C. of 24 hours or more is adhered to a fiber mat mainly containing coconut fiber, and the water content of the fiber mat is reduced. A method for producing a fiberboard, comprising performing thermocompression molding in a state of not more than 40% by weight of a dry weight of a fiber mat. (2) The water content of the fiber mat is 30% of the dry weight of the fiber mat.
Characterized in that the thermocompression molding is carried out at a weight percentage of not more than
The method for producing a fiberboard according to (1). (3) After attaching the amino resin-containing composition to the fiber mat, the fiber mat is dried so that the water content of the fiber mat is 40% by weight or less of the dry weight of the fiber mat. The method for producing a fiberboard according to (2). (4) The pot life of the amino resin curing catalyst at 40 ° C. is 24 to
The method for producing a fiberboard according to any one of the above (1) to (3), which is 500 hours. (5) Any one of the above (1) to (4), wherein the content of the amino resin curing catalyst in the composition is 0.1 to 10 parts by weight based on 100 parts by weight of the amino resin. 3. The method for producing a fiberboard according to item 1. (6) The fiber according to any one of (1) to (5), wherein the amount of the amino resin used is 5 to 100 parts by weight based on 100 parts by weight of the fiber constituting the fiber mat. Plate manufacturing method. (7) The method for producing a fiberboard according to any one of the above (1) to (6), wherein the coconut fiber is a fiber defibrated from oil palm. (8) a fiber mat, after laminating a knitted woven fabric and / or a non-woven fabric, after adhering the amino resin-containing composition, or a fiber mat to which the amino resin-containing composition is adhered,
The fiberboard according to any one of the above (1) to (7), wherein after laminating a knitted woven fabric and / or a nonwoven fabric to which a composition containing a curable resin is adhered, heat compression molding is performed. Production method. (9) The fiber according to any one of (1) to (8), wherein the amino resin is at least one selected from the group consisting of urea resins, melamine resins, and urea-melamine copolymer resins. Plate manufacturing method. (10) A fiberboard produced by the method according to any one of the above (1) to (9) and having a bending strength of 3 to 50 N / mm ² . (11) The moisture permeability coefficient is 0.1 to 10 μg / (m ² · s · Pa)
The fiberboard according to the above (10), wherein

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a fiber board 1 according to the present invention. The fiberboard 1 is made of a fiber mat 2 mainly composed of coconut fibers.
And a cured amino resin.

The coconut fibers used in the present invention include coconut palm, oil palm, sago palm, date palm, scabbard, nipa palm, sugar palm, pea palm, palm, burdock, black jug, and the like. Fibers such as petiole base fiber and mesocarp fiber, including fibers obtained by defibrating empty fruit clusters of oil palm. Further, a mixture of two or more types of coconut fibers is also included.

In the present invention, it is preferable to use oil palm palm fiber as the palm fiber. The palm fiber of the oil palm is obtained by defibrating empty fruit clusters of the oil palm. The oil palm 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 reduced and the cost can be reduced. For example, coconut palms require a long period and a large amount of energy to be immersed in water for a long period of time to soften the coconut shell, and then mechanically defibrated into fibrous form. On the other hand, in oil palm, since the empty fruit clusters which are originally aggregated in a fibrous state are defibrated, there is no need for immersion in water and the energy required for defibration is very small. In addition, the palm fiber of oil palm is less dust-producing than the palm fiber of coconut palm, and it is preferable because the working environment is prevented from deteriorating in handling. In addition, oil palm oil is exploited from the oil palm fruit, but the empty fruit bunches remaining after harvesting this fruit currently have no specific use and are usually doomed to be discarded, so they are low cost. Available.

In addition to the coconut fiber, other fibers may be blended. For example, natural vegetable fibers such as hemp fiber and bamboo fiber can be mixed with the coconut fiber and used. In this case, while the diameter of the palm fiber is about 100 to 600 μm, the diameter of the hemp fiber is about 5 to 30 μm, and the diameter of the bamboo fiber or the like is 10 to 200 μm.
Since it is as thin as μm, vegetable natural fibers such as hemp fiber and bamboo fiber are entangled at intersections of palm fibers and the like, and the bonding strength between palm fibers increases. These fibers are preferably used in an amount of 5 to 30 parts by weight based on 100 parts by weight of the coconut fiber.

In order to form the fiber mat 2, coconut fiber or the like is entangled with a nonwoven fabric or a three-dimensional knitted structure by a needle punch or the like to increase the peel strength, and if necessary, a press or a hot press or the like is used. Makes the fiber mat 2 denser. In addition, the thickness of the fiber mat 2 is usually 5 mm to 20 mm when performing thermocompression molding, and it is easy to use. However, it is needless to say that the thickness is not limited to this and may be arbitrarily set according to the application. A plurality of sheets may be used.

Among the above-mentioned coconut fibers, oil palm coconut fibers have a diameter as large as about 100 to 600 μm, and when used to make a fiber mat 2, depending on the fiber packing density,
A gap having a size of, for example, about 100 μm to 5 mm, preferably about 200 μm to 3 mm is formed between the fibers.
Therefore, the moisture permeability of the fiber mat 2 obtained from the palm fiber of oil palm is extremely good.

Further, the palm fiber of the oil palm has a high rigidity of a simple substance, a large diameter as described above, a long bend of about 5 to 30 cm, and a large entanglement between the fibers. Therefore, the fiberboard 1 obtained from the palm fiber of oil palm has excellent holding power when nailed.

The fiber mat 2 containing such palm fibers as a main component contains a cured amino resin to form a fiber board 1. The cured amino resin serves as an adhesive between the fibers in the fiber mat 2 and a binder for the fiber mat 2. With such a configuration, the strength of the fiberboard 1 is improved. Such a fiber board 1 is generally obtained by adhering a composition containing an amino resin and an amino resin curing catalyst to a fiber mat 2 and curing the composition. In most cases, the composition is in the form of an aqueous solution. Used in.

The amino resin used in the present invention includes:
For example, a urea resin (urea resin), a melamine resin, a urea-melamine copolymer resin, a benzoguanamine resin, and an acetoguanamine resin are exemplified. Among these, the urea resin is particularly inexpensive and is cured by curing. This is preferred because the adhesion between the fibers in 2 becomes particularly good. The melamine resin is particularly preferably used because it has good water resistance, and the urea-melamine copolymer resin is particularly preferable because it is inexpensive and has good water resistance.

The fiberboard 1 of the present invention is manufactured, for example, by the following method. First, an amino resin-containing composition containing an amino resin, an amino resin curing catalyst, and water as a solvent is prepared, and is attached to the fiber mat 2. The moisture content of the fiber mat 2 before the heat compression molding is 40% by weight, preferably 30% by weight or less, more preferably 20% by weight, based on the dry weight of the fiber mat 2 to which the amino resin is not attached.
By performing thermocompression molding in a state of not more than weight%, the amino resin is cured while simultaneously bringing more fibers in the fiber mat 2 into contact with each other by compression, and the fibers are bonded to each other.

When the moisture content of the fiber mat 2 to which the amino resin-containing composition has adhered exceeds 40% by weight based on the dry weight of the fiber mat 2 to which the amino resin has not adhered, the fiber mat 2 is dried to obtain the moisture content. The amount is not more than 40% by weight.

When the water content exceeds 40% by weight,
In order to achieve sufficient curing, a long thermocompression molding time is required, and a molding cycle is prolonged, thereby reducing productivity (for example, a thermocompression molding method in which a fiberboard having a thickness of 9 mm is used for sufficient adhesion between fibers). The molding time is 10 minutes or more). Further, if the heat compression molding time is short, the strength of the obtained fiberboard is inferior.

The amino resin curing catalyst used here has a pot life at 40 ° C. of 24 hours or more, preferably 24 to 1000 hours, more preferably 24 to 5 hours.
A catalyst of 00 hours, particularly preferably 48 to 240 hours, is used. Here, the pot life at 40 ° C. is 40
This refers to the maximum time during which the amino resin-containing composition cannot be handled due to viscosity increase or solidification at 0 ° C, and the composition can be adhered to the fiber mat. Pot life at 40 ° C is 24
Examples of the amino resin curing catalyst for longer hours include Catanit A and Catanit C manufactured by Nitto Chemical, and Catalyst 376 manufactured by Dainippon Ink.

Amino resin curing catalysts having a pot life of less than 24 hours at 40 ° C. include, for example, ammonium chloride and ammonium sulfate. If drying is performed before heat compression molding in order to reduce the water content of the resin, the action of these curing catalysts will occur during this drying step, causing the amino resin to thicken or harden. Compression of the fiber mat does not bond the fibers sufficiently. As a result,
Insufficient strength of fiberboard. Further, for example, when an amino resin is used under a condition in which the temperature exceeds 35 ° C., such as in summer, the amino resin is easily solidified in the piping of the apparatus, which causes a trouble. Further, the pot life at 40 ° C. is practically 1000 hours, and there is a concern that the curing rate at the time of heat compression molding may be slowed with an amino curing catalyst in which the pot life at 40 ° C. exceeds 1000 hours. However, this is not preferable in practical use.

In the above-mentioned drying step, the drying temperature and the drying time depend on the amount of moisture in the fibers constituting the fiber mat, the amount of the composition solution attached, and the amount of moisture in the solution. 30 minutes. Therefore, the above 4
The amino resin curing catalyst having a pot life at 0 ° C. of 24 hours or more preferably has a pot life at 60 ° C. of 30 minutes or more. As the drying means, a hot air dryer or the like is employed.

The temperature, time and compression ratio during hot compression molding depend on the type of amino resin and catalyst used, the amount used, the thickness of the fiberboard, the strength required for the fiberboard, and the like. To 200 ° C., the time is 3 to 15 minutes, and the compression ratio is about 1/10 to 1/2.

The amount of the amino resin curing catalyst is preferably 0.1 to 10 parts by weight per 100 parts by weight of the amino resin.
Parts by weight, more preferably 0.3 to 3 parts by weight. When the amount of the curing catalyst is less than 0.1 part by weight, the degree of curing of the amino resin is low, and the strength of the fiberboard 1 is inferior. There is no improvement and the cost increases, which is not preferable.

The amount of the amino resin used is preferably 5 to 10 parts by weight based on 100 parts by weight of the fibers constituting the fiber mat 2.
0 parts by weight, more preferably 5 to 30 parts by weight, particularly preferably 10 to 30 parts by weight. 5 amino resin used
If the amount is less than the weight part, the amount used is too small.
The density may be low and the strength may be insufficient. For example, when the density is less than 0.2 g / cm ³ , the bending strength is 3 N / m 3.
It is low when it is less than m ² . Conversely, if the usage exceeds 100 parts by weight, the density of the fiberboard 1 may increase due to too much usage, resulting in insufficient air permeability.
When the thickness exceeds 9 g / cm ³ and the thickness is 9 mm, the moisture permeability coefficient is 0.1.
μg / (m ² · s · Pa), which is low, which is not preferable because the possibility of dew condensation increases when used as a windproof layer. The composition is adhered to the fiber mat 2 such that the amount of the amino resin used falls within the above range.

The content of the amino resin in the composition is determined as follows.
In consideration of drying to be 0% by weight or less, the higher the amino resin content (that is, the solid content concentration of the amino resin), the better. However, if it is too high, the viscosity becomes high and handling becomes difficult. About 65% by weight is preferable.

Depending on the amount of water contained in the fiber used as the raw material of the fiber mat 2 and the content of the amino resin in the composition, the fiber mat after the amino resin-containing composition is adhered to the fiber mat 2 May have a moisture content of less than 40% by weight, in which case it is not necessary to dry before hot compression molding.

Various additives may be further added to the composition described above, for example, plasticizers, fillers, reinforcing materials, anti-sagging agents, coloring agents, anti-aging agents, adhesion promoters, curing catalysts, waxes, A physical property modifier and the like can be blended. In addition, konjac, flour, starch and the like may be added as an adhesion-imparting agent.

Since a large gap is formed between the fibers of the fiber mat 2, when the amino resin-containing composition is supplied to the fiber mat 2 by spraying or dipping, the composition is supplied to the fiber mat 2 through the gap. Adheres evenly to all fibers of Then, when the water content of the fiber mat 2 is 40% by weight or less with respect to the dry weight of the fiber mat 2 (dry as necessary), the fibers in the fiber mat 2 are brought into contact by compression. Increases, and at the same time, the amino resin is cured by heat. As a result, the fibers are strongly adhered to each other, so that a uniform and high-strength fiberboard 1 can be obtained. In this fiber board 1, a relatively large gap is formed between the fibers, so that the moisture permeability is extremely good. Therefore, when this fiberboard 1 is used for the windproof layer, it is possible to smoothly transmit water vapor to the ventilation layer due to high moisture permeability, and it is possible to stably hold the heat insulating layer due to high strength. The structural portion around the windbreak layer can be reinforced by the plate 1.

For manufacturing the fiberboard 1 of the present invention, for example, an apparatus shown in FIG. 2 can be used. This device is
A required number of hoppers 5 are provided in series in the belt traveling direction above the upstream side of the belt conveyor 4, and a needle punch device 6 is provided downstream of the hopper 5, and spray guns 7 are provided above and below the downstream belt conveyor 4. 7 is installed. Fibers constituting a fiber mat such as coconut fiber are put into the hopper 5, and a composition containing an amino resin and an amino resin curing catalyst is supplied to the spray gun 7 under pressure. Then, after the coconut fibers are dropped and supplied from the respective hoppers 5 onto the belt conveyor 4 simultaneously with the operation of the belt conveyor 4, the fiber mat 2 is formed by performing a process of needle-punching and entanglement of the fibers by the needle punching device 6, Next, the above-mentioned amino resin-containing composition is injected and supplied from the spray guns 7 and 7. If necessary, the fiber mat is dried so that the water content of the fiber mat is 40% by weight or less of the dry weight of the fiber mat. Get. For heat compression molding,
There are a continuous molding method using a thermocompression roller or a belt press, and a batch molding method using a single-stage or multi-stage press. Instead of spraying and supplying the amino resin-containing composition to the fiber mat 2, the fiber mat 2 may be adhered by dipping the fiber mat 2 in the composition.

The thickness of the fiberboard 1 of the present invention is appropriately selected according to the strength and moisture permeability required of the fiberboard 1, but is preferably 3 to 25 mm, more preferably 9 to 20 mm. When the thickness is less than 3 mm, the strength may be insufficient. On the other hand, when the thickness is more than 25 mm, the heat compression molding becomes difficult, which is not preferable.

The density of the fiberboard 1 is appropriately selected according to the strength and moisture permeability required of the fiberboard 1, but is preferably 0.2 to 1.5 g / cm ³ , more preferably 0.1 to 1.5 g / cm ³ . 3
１1 g / cm ³ , particularly preferably 0.35 to 0.7 g
/ Cm ³ . When the density of the fiberboard 1 is less than 0.2 g / cm ³ , for example, the bending strength is less than 3 N / mm ^2, and the quality as a sealing board among the JIS-A-5905 fiberboards is not satisfied. 1.5g / cm
If it exceeds ³ , the air permeability is insufficient, and the fiber board is more likely to be compressed and broken due to an increase in the compressive force, so that it is difficult to obtain by heating and compression, and it becomes too heavy to carry. It is not preferable because the handling property is deteriorated.

The basis weight of the fiberboard 1 is set according to the thickness and density. For example, when the thickness of the fiberboard 1 is 9 mm, the density is 0.2 g / cm ³ and the basis weight is 1.8 kg / m ^2. And at a density of 1.5 g / cm ³ a basis weight of 13.5 k
g / m ² .

The fiber board 1 of the present invention has excellent strength, and its bending strength is 3 to 50 N / mm ² , preferably 10 to 40 N / mm ² , and more preferably 15 to 30 N / mm ² .
/ Mm ² . In the present invention, the bending strength is measured according to the measuring method of JIS-A-5905. The fiberboard 1 having the above-mentioned bending strength is mainly subjected to thermocompression molding using the specific amino resin curing catalyst as described above and in a state where the water content of the fiber mat is equal to or less than a specific amount (drying as necessary). It is obtained by doing.

The fiber board 1 of the present invention has moisture permeability in addition to strength, and its moisture permeability coefficient is preferably 0.1 to 10 μg / (m ² · s · Pa). Preferably, it has a performance of 0.2 to 8 µg / (m ² · s · Pa), particularly preferably 0.5 to 5 µg / (m ² · s · Pa). In the present invention, the moisture permeability coefficient is
It is measured according to the measuring method of JIS-Z-0208.

In the present invention, as described above,
The moisture content of the fiber mat is
Heat compression (dry if necessary) at or below the fixed amount
In addition to the manufacturing method for molding,
Amount of Mino resin, thickness of fiber used for fiber mat, heat
By selecting the compression ratio at the time of compression molding, etc.,
Density, in other words, the size of the gap between the fibers, falls within the above range.
Control for both strength and moisture permeability
A fiberboard can be obtained. Specifically, it is the main component
The thickness of the palm fiber is about 100 to
Mino resin to 100 parts by weight of fiber constituting fiber mat
5 to 100 parts by weight, the compression ratio at the time of hot compression molding is 1 /
10 to 1/2, the density of the fiberboard is about 0.2 to 1.5
g / cm ^ThreeBy controlling the fiberboard 1
The gap is preferably about 1 to 100 μm, more preferably
It can be about 5 to 50 μm, and the above bending strength and
It has air permeability and moisture permeability, but has ventilation but does not allow rain to pass.
It is possible to manufacture a fiberboard 1 having excellent strength.
You. Therefore, according to this fiberboard 1, depending on the construction situation
An optimal windbreak layer can be formed.

In the present invention, the fiber mat 1 is laminated with a knitted fabric and / or nonwoven fabric 3 as shown in FIG. The material may be adhered to the fiber mat 2 and dried as needed in the same manner as described above to reduce the moisture content of the fiber mat 2 to 40% by weight or less, followed by hot compression molding. In such a lamination, a knitted woven fabric and / or a nonwoven fabric 3 may be laminated on one or both sides of the fiber mat and between the fiber mats. Alternatively, for example, as shown in FIG. The woven fabric and / or the nonwoven fabric 3 may be sequentially and alternately laminated.

After the amino resin-containing composition is adhered to the fiber mat 2, the fiber mat 2 and the knitted and / or nonwoven fabric 3 to which the curable resin-containing composition has been adhered are laminated. Similarly to the above-mentioned method, the water content of the fiber mat 2 is reduced to 40% by weight by drying if necessary.
The following conditions may be adopted and thermocompression molding may be performed. In such lamination, the knitted fabric and / or nonwoven fabric 3 may be laminated on one or both sides of the fiber mat and between the fiber mats, or the plurality of fiber mats 2 and the knitted fabric and / or nonwoven fabric 3 are alternately sequentially arranged. May be laminated. here,
The curable resin to be attached to the knitted fabric and / or the nonwoven fabric 3 is preferably an amino resin, as in the case of the fiber mat 2, and in particular, an amino resin curing catalyst having a pot life of 24 hours or more was used in combination. Preferably, a composition as described above is deposited.

Further, the amino resin-containing composition is adhered to the fiber mat 2 and, if necessary, dried to reduce the water content of the fiber mat 2 to 40% by weight or less.
The knitted fabric and / or the nonwoven fabric 3 to which the composition containing the curable resin composition has adhered may be laminated and subjected to thermal compression molding. Here, as the curable resin contained in the composition adhered to the knitted fabric and / or the nonwoven fabric 3, an amino resin, a phenol resin, a urethane resin, or the like can be used.

Further, at the time of producing the fiber mat 2, a knitted fabric and / or a non-woven fabric 3 are arranged between palm fibers or above, below, or above and below palm fibers, and this is subjected to a treatment such as needle punching. May be used in which the knitted fabric and / or the nonwoven fabric 3 are arranged.

The composition containing the amino resin and the amino resin curing catalyst functions as an adhesive between the fibers in the fiber mat 2 and a binder for the fiber mat 2, and at the same time, the knitted and / or nonwoven fabric 3 itself. A binder,
It functions as an adhesive between the knitted and / or nonwoven fabric 3 and the fiber mat 2 and also as a binder for the entire fiberboard 1.

The knitted and / or nonwoven fabric 3 used in the present invention is composed of plant fibers, synthetic fibers, mineral fibers and the like.

As the knitted fabric 3, as shown in FIG. 3, there is exemplified a cloth formed by knitting hemp yarn in which hemp fibers are twisted vertically and horizontally. Here, the hemp includes those that take the skin fibers such as jute, flax, kenaf, and ambassador, and those that take the tissue fibers such as manila, sisal, New Zealand and Mauricias. Hemp fibers are fibers obtained by defibrating these hemp. Knitted fabrics include jute cloth, which is a cloth formed of jute.

The knitted fabric 3 has excellent strength because it is knitted with hemp fiber or the like having a high tensile strength and tensile modulus. Further, the strength of the nonwoven fabric itself is inferior to that of the knitted fabric itself such as hemp, but since the nonwoven fabric can hold a greater amount of the amino resin-containing composition than the knitted fabric, the fiberboard 1
Can be given strength. The fibers constituting the nonwoven fabric 3 are not particularly limited, but natural fibers are preferable in view of the bonding force with the fiber mat 2, and synthetic fibers such as nylon, polypropylene, polyethylene, and polyester may be mixed as necessary. The nonwoven fabric 3 is made of a web made of hemp fiber by a dry papermaking method, hardened with an adhesive such as a latex of natural rubber, and dried and finished, and a thin nonwoven fabric formed by a wet papermaking method. Also includes paper formed by defibrating fibers and forming by wet papermaking. These knitted and woven fabrics 3 have air permeability,
It is excellent in moisture permeability. In a single fiber board, a knitted fabric and a nonwoven fabric may be used in combination of two or more.

When the knitted fabric 3 is made of hemp cloth,
Examples include plain weave, twill weave, satin weave, nanako weave (regular,
It is preferable to select from
Woven and twill weave are particularly preferred. Plain knitting, rubber as knitting structure
It is selected from knitting and the like. Examples of yarns used here include
Select from jute count 7.5 to 40 for ease of hand
Is preferred. Also, the basis weight is preferably 100 g / m
^Two~ 1200g / m^TwoDegree, more preferably 100 g /
m^Two~ 1000g / m^TwoAnd particularly preferably 100 g / m
^Two~ 600g / m^TwoIt is. The basis weight is 100 g / m^TwoLess than
Then, for example, the dimensional change in the length direction of the fiber board 1 when absorbing water
Exceeds 0.5% in the fiberboard of JIS-A-5905.
The quality of the sheathing board is no longer satisfied,
0 g / m ^TwoDimensional stability and reinforcement effect
The cost is high despite the lack of greatness, so
Not good.

The weight of the hemp cloth 3 laminated on the fiber mat 2 or placed inside the fiber mat 2 can be selected by a combination of the basis weight and the number of laminations depending on physical properties such as dimensional stability and strength required for the fiber board 1. , For 100 parts by weight of coconut fiber,
It is preferably 5 to 50 parts by weight, more preferably 5 to 30 parts by weight, particularly preferably 10 to 25 parts by weight. When the weight part of the hemp cloth 3 is less than 5 parts by weight, for example, the dimensional change in the length direction of the fiber board 1 when absorbing water exceeds 0.5%, and
Exceeding 0 parts by weight is not preferred because the cost increases.

When the knitted fabric and / or the nonwoven fabric 3 are arranged on the surface of the fiber mat 2, especially on both surfaces, a so-called sandwich structure (a structure in which the upper and lower portions of the main structure are reinforced with a material having higher strength or rigidity than the main structure) is used. As a result, the bending strength and the bending elastic modulus of the fiberboard 1 increase. On the other hand, when the knitted fabric and / or the nonwoven fabric 3 are arranged between the fiber mats 2 or inside the fiber mat 2, the tensile strength and the tensile modulus, the shear strength and the shear modulus of the fiberboard 1, and the in-plane compressive strength (Strength when receiving a compressive force in a plane stress state) and in-plane compressive elasticity (elastic modulus when receiving a compressive force in a plane stress state).

Further, when the knitted fabric 3 is formed of hemp fibers such as hemp cloth, the dimensional change upon water absorption and moisture absorption is small, so that when the knitted fabric 3 is laminated on the fiber mat 2 or placed inside the fiber mat 2, In addition, the dimensional change of the fiber board 1 at the time of water absorption and moisture absorption is small, and the strength decrease at the time of water absorption and moisture absorption is small, which is preferable.

As described above, by laminating the fiber mat 2 and the knitted woven fabric and / or the nonwoven fabric 3 or by arranging the knitted woven fabric and / or the nonwoven fabric 3 inside the fiber mat 2, the strength of the fiberboard 1 is improved. Can be further improved. Further, by laminating the knitted fabric and / or the nonwoven fabric 3 on at least one surface of the fiber mat 2, the surface properties of the fiber board 1 can be changed, so that finishing is not required or when a finishing material is pasted on the surface. Of the finishing material can be improved. If the knitted fabric and / or the nonwoven fabric 3 are made of a material having a high moisture permeability such as hemp fiber or the like, a high moisture permeability can be obtained as a whole fiber board without impairing the excellent moisture permeability of the fiber mat 2. . Therefore, if a windbreak layer is formed using such a fiberboard 1,
Water vapor can be smoothly transmitted to the ventilation layer due to high moisture permeability, and the heat insulation layer can be held stably with higher strength, and the fiberboard 1 can reinforce the structure around the windbreak layer.

When the fiber mat 2, the knitted woven fabric and / or the non-woven fabric 3 are all vegetable natural fibers, the unevenness of the surface is larger than that of the artificial fibers or the like. And the so-called anchor effect (adhesive penetrates into voids on the surface of the material and solidifies and acts like a nail or wedge), thereby improving the bonding between fibers by curing the amino resin. ing.

When it is necessary to further improve the water resistance of the knitted fabric and / or the nonwoven fabric 3, wax, silicon or the like may be applied to the surface of the knitted fabric and / or the nonwoven fabric 3. In addition, flame retardants, colorants,
A bactericidal agent, a preservative, a termiticide, or the like may be applied as necessary.

Further, in the above embodiment, only the fiberboard 1 having a rectangular shape in a front view and a substantially constant thickness has been described. Good. In that case, only the final shape is different, and the above-described embodiment of the fiberboard 1 can be applied as it is, and the same operation and effect can be obtained.

The use of the fiberboard of the present invention is not limited to the windproof layer, but is excellent in strength, moisture permeability, and productivity. Base material, ceiling material, house interior material, interior base material, architectural insulation material, rim material, sound insulation material, sound absorbing material, cushioning material, shock absorbing material, concrete formwork material, loading pallets, automotive interior materials It can also be used as a base material for vehicle interiors such as automobiles, furniture material, and the like.

[0056]

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

<Measurement Method> Moisture content of fiber mats Moisture content of fiber mats before amino resin adhesion A (% by weight) The fiber mats before amino resin adhesion are dried at 105 ° C. until a constant weight is obtained, and the weights before and after the drying are calculated from the following formula using the weight before and after the drying. . A = (weight loss on drying of fiber mat before amino resin adhesion / weight after drying of fiber mat before amino resin adhesion) × 100 moisture content of fiber mat after amino resin adhesion B (% by weight) It is calculated from the following formula. B = ｛(amount of water in attached amino resin) × 100 /
(Weight of fiber mat before amino resin adhesion × 100 / (1
00 + A))｝ + A Water content C (% by weight) of the fiber mat after completion of the drying step C = （((moisture content in amino resin adhered) − (loss on drying after amino resin adherence)) × 100 / (amino Weight of fiber mat before resin adhesion x 100 / (100 + A)) +
A

2. Fiberboard Density After the fiberboard is cut into a rectangular parallelepiped shape, the fiberboard weight and fiberboard dimensions (thickness, length, width) are measured and determined from the weight and dimensions.

3. Flexural strength of fiberboard Measured according to the method of measuring a fiberboard according to JIS-A-5905.

4. Moisture permeability coefficient of fiberboard Measured according to JIS-Z-0208 moisture permeability test method for moisture-proof packaging material.

Example 1 A urea resin having a solid content of 65% by weight (35% by weight is water) was mixed with 2 parts by weight of Nitto Chemical's Catanit A (imide / disulfonic acid and sulfamic acid) based on 100 parts by weight of the resin solids. Of 2-amino-2-methyl-propanol) and 150 parts by weight of water based on 100 parts by weight of the resin solids. Immediately after the composition was prepared, the composition was sprayed onto a fiber mat composed of oil palm palm fiber (having a moisture content of 8% by weight) having a basis weight of 3.6 kg / m ² by a spray method, and solidified with respect to 100 parts by weight of the palm fiber. After 20 minutes by weight of the urea resin was attached to the fiber mat and the water content of the fiber mat was adjusted to 53% by weight, the fiber mat was dried with a dryer at 100 ° C. for 10 minutes to reduce the water content of the fiber mat to 12% by weight. . next,
This fiber mat was subjected to thermocompression molding using a press machine at 180 ° C. for 6 minutes to obtain a 9 mm-thick fiberboard.

Example 2 To a urea resin having a solid content of 65% by weight (35% by weight is water), 2 parts by weight of Catanit A manufactured by Nitto Chemical and 100 parts by weight of a resin solids were added to 100 parts by weight of the resin solids. For 15
0 parts by weight of water were mixed. Next, after preparing this composition,
After standing in a tank of a spray device at 40 ° C. for 24 hours, it is sprayed on a fiber mat composed of oil palm palm fiber (having a moisture content of 8% by weight) with a basis weight of 3.6 kg / m ² by a spray method, and the palm fiber is 100 weight 20 parts by weight of a urea resin in solid content was attached to each part, and the moisture content of the fiber mat was adjusted to 53% by weight.
After drying for 10 minutes, the water content of the fiber mat was adjusted to 10% by weight.
Next, this fiber mat was pressed at 180 ° C.
The composition was heat-compressed under the conditions of 1 minute to obtain a fiberboard having a thickness of 9 mm.

Example 3 A melamine resin having a solid content of 65% by weight (35% by weight is water) was mixed with 3 parts by weight of Catalyst 376 (organic amine compound) manufactured by Dainippon Ink for 100 parts by weight of the resin solids. 150 parts by weight of water was mixed with 100 parts by weight of the resin solid content. Next, immediately after preparing this composition, the basis weight of 3.2 k
g / m ² of oil palm palm fiber (moisture content 8% by weight) is sprayed onto a fiber mat by a spraying method, and palm fiber 10
20 parts by weight of melamine resin in solid content is attached to 0 parts by weight, and the moisture content of the fiber mat is adjusted to 53% by weight. Then, the fiber mat is dried by a dryer at 100 ° C. for 10 minutes to reduce the moisture content of the fiber mat. It was 13% by weight. Separately, the above-mentioned melamine resin composition was adhered to two jute cloths having a basis weight of 0.32 kg / m ^{2 at} a solid content of 10 parts by weight based on 100 parts by weight of the jute cloth. Subsequently, the undried jute cloth, the fiber mat, and the undried jute cloth were stacked in this order, and these were then placed at 180 ° C. by a press machine.
Heat compression molding was performed under the conditions of -6 minutes to obtain a fiberboard having a thickness of 9 mm.

Example 4 In Example 1, the curing catalyst was changed from Catanite A to Catanite C (imide / disulfonic acid and 2-amino-2-
Methyl-propanol mixture),
A fiberboard having a thickness of 9 mm was obtained in the same manner as in Example 1.

Comparative Example 1 For a urea resin having a solid content of 65% by weight (35% by weight is water), 2 parts by weight of Catanit A manufactured by Nitto Chemical and 100 parts by weight of a resin solid content were added to 100 parts by weight of a resin solid content. For 15
0 parts by weight of water were mixed. Immediately after the composition was prepared, the composition was sprayed onto a fiber mat composed of coconut palm oil (having a moisture content of 8% by weight) with a basis weight of 3.6 kg / m ² by a spray method. 20 parts by weight of urea resin are adhered per minute, and the water content of the fiber mat is reduced to 53 parts by weight.
% By weight. Next, this fiber mat was subjected to thermocompression molding using a press machine at 180 ° C. for 6 minutes to obtain a 9 mm-thick fiberboard.

COMPARATIVE EXAMPLE 2 A urea resin having a solid content of 65% by weight (35% by weight is water) was prepared by adding 1 part by weight of ammonium chloride to 100 parts by weight of resin solids and 150 parts by weight to 100 parts by weight of resin solids. Of water were mixed. Next, immediately after this composition was prepared, it was sprayed onto a fiber mat composed of oil palm palm fiber (water content: 8% by weight) having a basis weight of 3.6 kg / m ² by a spray method.
20 parts by weight of urea resin is adhered to 100 parts by weight of coconut fiber as a solid matter, and the water content of the fiber mat is adjusted to 53% by weight.
After drying for a minute, the moisture content of the fiber mat was adjusted to 11%. Next, this fiber mat was subjected to thermocompression molding using a press machine at 180 ° C. for 6 minutes to obtain a 9 mm-thick fiberboard.

Comparative Example 3 A urea resin having a solid content of 65% by weight (35% by weight was water) was prepared by adding 1 part by weight of ammonium chloride to 100 parts by weight of resin solids and 150 parts by weight to 100 parts by weight of resin solids. Of water were mixed. Next, when this composition was left in a tank of a spray device at 40 ° C. for 24 hours, the composition was solidified and could not be sprayed by the spray method.

Comparative Example 4 A urea resin having a solid content of 65% by weight (35% by weight was water) was prepared by adding 1 part by weight of ammonium chloride to 100 parts by weight of resin solids and 150 parts by weight to 100 parts by weight of resin solids. Of water were mixed. Next, immediately after this composition was prepared, it was sprayed onto a fiber mat composed of oil palm palm fiber (water content: 8% by weight) having a basis weight of 3.6 kg / m ² by a spray method.
20 parts by weight of urea resin was adhered to 100 parts by weight of coconut fiber as a solid content, and the water content of the fiber mat was adjusted to 53% by weight. Next, the fiber mat is pressed 180
Thermocompression molding was performed at a temperature of -12 minutes to obtain a fiberboard having a thickness of 9 mm.

Comparative Example 5 For a urea resin having a solid content of 65% by weight (35% by weight is water), 2 parts by weight of Catanit A manufactured by Nitto Chemical and 100 parts by weight of a resin solid content were added to 100 parts by weight of a resin solid content. For 15
0 parts by weight of water were mixed. Immediately after the composition was prepared, the composition was sprayed onto a fiber mat composed of oil palm palm fiber (having a moisture content of 8% by weight) having a basis weight of 3.6 kg / m ² by a spray method, and solidified with respect to 100 parts by weight of the palm fiber. In 20 minutes, 20 parts by weight of urea resin was adhered, and the water content of the fiber mat was adjusted to 53% by weight. Next, this fiber mat was subjected to thermal compression molding using a press machine at 180 ° C. for 12 minutes to obtain a 9 mm-thick fiberboard.

Comparative Example 6 For a melamine resin having a solid content of 65% by weight (35% by weight is water), 3 parts by weight of Catalyst 376 manufactured by Dainippon Ink and 100 parts by weight of resin solids were added to 100 parts by weight of resin solids. Was mixed with 150 parts by weight of water. Immediately after this composition was prepared, it was sprayed on a fiber mat composed of oil palm palm fibers (water content: 8% by weight) having a basis weight of 3.2 kg / m ² by a spraying method.
A weight part of melamine resin was adhered, and the water content of the fiber mat was adjusted to 53% by weight. Separately, basis weight 0.32kg
The above-mentioned melamine resin composition was adhered to ^two jute cloths having a solid content of 10 parts by weight based on 100 parts by weight of the jute cloth. Next, this undried jute cloth,
After laminating the fiber mat and the undried jute cloth in this order, these were hot-pressed at 180 ° C. for 6 minutes using a press to obtain a fiberboard having a thickness of 9 mm.

Comparative Example 7 A fiberboard having a thickness of 9 mm was obtained in the same manner as in Comparative Example 1, except that the curing catalyst was changed from Catanit A to Catanit C.

Table 1 shows the production conditions of the fiberboard obtained from Examples 1 to 4 and Comparative Examples 1 to 7, and Table 2 shows the density, bending strength and moisture permeability of the obtained fiberboard.

[0073]

[Table 1]

[0074]

[Table 2]

From Tables 1 and 2, the fiber boards obtained in Examples 1 to 4 had good strength and good moisture permeability, but Comparative Examples 1, 6 and 7 showed that Since the water content of the previous fiber mat exceeded 40% by weight and the pressing time was as short as 6 minutes, the strength of the obtained fiberboard was inferior. In Comparative Examples 4 and 5, the press time was doubled to 12 minutes because the water content of the fiber mat before the heat compression molding exceeded 40% by weight, but the fiber board obtained in Examples 1 to 4 was still used. The strength was slightly inferior in comparison. In addition, since the press time is long, the heat compression molding cycle is long, and the productivity is poor. In Comparative Example 2, the fiber mat was dried so that the water content of the fiber mat before the heat compression molding was 40% by weight or less. However, the amino resin curing catalyst used had a pot life of less than 24 hours. The amino resin was cured during drying, and the strength of the obtained fiberboard was poor.

[0076]

As described above, according to the method for producing a fiberboard of the present invention, the strength and the air permeability are good, the cycle of the heat compression molding is short, and the productivity is good. A fiberboard suitable for a windbreak layer can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view of a fiber board according to an embodiment.

FIG. 2 is an explanatory view showing a method for producing a fiberboard of the embodiment.

FIG. 3 is an enlarged perspective view showing an example of a knitted fabric used in another embodiment.

FIG. 4 is a cross-sectional view of a fiber board according to another embodiment.

[Description of Signs] 1 Fiber board 2 Fiber mat 3 Hemp cloth (Knitted fabric) 4 Belt conveyor 5 Hopper 6 Needle punch device 7 Spray gun

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI // B29K 61:20 105: 06

Claims (11)

[Claims] 1. A fiber mat mainly composed of coconut fibers,
A composition containing an amino resin and an amino resin curing catalyst having a pot life at 40 ° C. of 24 hours or more is adhered, and the water content of the fiber mat is 40% by weight or less of the dry weight of the fiber mat. And a method of manufacturing a fiberboard, wherein the fiberboard is subjected to heat compression molding. 2. The method for producing a fiberboard according to claim 1, wherein the fiber mat is heat-compressed at a moisture content of 30% by weight or less of the dry weight of the fiber mat. 3. The method of claim 1, wherein after the amino resin-containing composition is attached to the fiber mat, the fiber mat is dried so that the moisture content of the fiber mat is 40% by weight or less of the dry weight of the fiber mat. Or the method for producing a fiberboard according to item 2. 4. The pot life of the amino resin curing catalyst at 40 ° C. is 24 to 500 hours.
The method for producing a fiberboard according to any one of claims 1 to 3. 5. The composition according to claim 1, wherein the content of the amino resin curing catalyst in the composition is 0.1 to 10 parts by weight based on 100 parts by weight of the amino resin. The method for producing a fiberboard according to the above. 6. The fiberboard according to claim 1, wherein the amino resin is used in an amount of 5 to 100 parts by weight based on 100 parts by weight of the fibers constituting the fiber mat. Manufacturing method. 7. The method for producing a fiberboard according to claim 1, wherein the coconut fibers are fibers defibrated from oil palm. 8. After laminating a fiber mat and a knitted woven fabric and / or a nonwoven fabric, after adhering an amino resin-containing composition, or containing a fiber mat to which an amino resin-containing composition is adhered, and a curable resin The method for producing a fiberboard according to any one of claims 1 to 7, further comprising laminating the knitted woven fabric and / or the nonwoven fabric to which the composition to be adhered is laminated, and then performing heat compression molding. 9. The method according to claim 1, wherein the amino resin is at least one selected from the group consisting of urea resins, melamine resins and urea-melamine copolymer resins.
9. The method for producing a fiberboard according to any one of items 1 to 8. 10. A flexural strength produced by the method according to claim 1 and having a bending strength of 3 to 50 N / mm ^2.
A fiberboard, characterized in that: 11. A moisture permeability coefficient of 0.1 to 10 μg / (m ²
S · Pa).