JP2003260705A - Heat accumulation type fiberboard and utilization method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiberboard having heat accumulation properties utilizable as a building interior material arranged so as to be pasted on the indoor side surfaces such as the wall, ceiling, floor or the like of a house to keep a comfortable room temperature for a long time even if heat preliminarily accumulated by a cooling and heating instrument or natural energy is gradually radiated to generate a large change in the open air temperature. <P>SOLUTION: This heat accumulating fiberboard is obtained by the thermal pressure bonding molding of a composition comprising microcapsules including a heat accumulating material, woody fibers and an adhesive. The film of the microcapsules preferably comprises a thermosetting urea/formalin resin or a melamine/formalin resin and the volume mean particle size thereof is preferably 10 μm or less. The heat accumulation material preferably has a melting point of 5-50°C and can be utilized as a building interior material for stabilizing a room temperature. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-retaining fiber board, a so-called particle board, a fiber board. The heat-retaining fiber board of the present invention is used for a building, a floor of a house or a building, a wall material, The present invention relates to a novel fiber board which can significantly save energy for cooling and heating by using it as an interior material such as a ceiling material.

[0002]

2. Description of the Related Art In recent years, global warming control has become more and more important worldwide, and as a countermeasure against it, a measure to reduce a large amount of carbon dioxide generated when a fossil fuel is burned becomes a big problem. There is. In particular, the amount of energy consumed to maintain the living environment and working environment of a building becomes enormous, and energy saving measures such as reduction and effective use thereof are indispensable.
Usually, in order to maintain the indoor temperature in a comfortable temperature range against fluctuations in the outside temperature, the confidentiality of the building itself is increased,
A measure of arranging a heat insulating material in a building such as a wall, a ceiling, or a floor is widely used, and a measure of suppressing heat transfer inside and outside the room is taken as much as possible.

On the other hand, energy such as solar heat and cooling / heating is stored as sensible heat in water or a part of the skeleton of a building, and a building material and a heat storage technology using a latent heat material have been proposed. As a specific example, JP-A-57-202493 discloses a heat storage body in which a spherical heat storage material is arranged in a building wall, and JP-A-58-237.
No. 9 discloses a heat storage and heat insulating material in which a synthetic resin tube filled with an inorganic heat storage material is inscribed.
17931 discloses a composite plate in which a heat storage material is implanted, and Japanese Patent Publication No. 29829/1990 proposes a combination of a heat insulating material and a latent heat storage material, but in general, the thermal conductivity of these latent heat storage materials is high. Since it was bad, the heat storage and heat dissipation characteristics deteriorated, and in many cases latent heat could not be used up efficiently. As a countermeasure, Japanese Patent Publication No. 6-33633 discloses a heat storage building material capable of encapsulating a plurality of latent heat storage materials and dispersing them in a base material to keep the heat radiation surface temperature substantially constant.

[0004]

The object of the present invention is to gradually dissipate the heat previously accumulated by the cooling / heating equipment or natural energy by arranging it by adhering it to the inside surface such as the wall, ceiling or floor of the house. Another object of the present invention is to provide a heat-retaining fiber board that can be used as an interior material for construction that maintains a comfortable room temperature for a long time even when a large change occurs in the outside air temperature.

[0005]

An object of the present invention is to use a heat storage fiberboard obtained by thermocompression molding a composition comprising microcapsules enclosing a heat storage material, wood fibers, and an adhesive as an interior material for construction. Achieved by

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The fiber board of the present invention is a wood-based fiber board generally used as a building material containing a high proportion of microcapsules containing a heat storage material. Laminated wood, particle board, fiber board, etc. are known as general wood-based processed materials. The laminated wood is a material in which small square wood is laminated and adhered in parallel with the fiber direction. Particleboard and fiberboard are plate-like products that are formed by adding and bonding an adhesive to wood, other plant fiber pieces, cut pieces, and crushed pieces. Fiber boards are classified into insulation boards, semi-hard boards, and hard boards according to their hardness.

Particle boards and fiber boards are characterized by being able to reuse wood-based waste materials generated during the dismantling of houses, as well as thinned wood, tree branches, planks and sawdust, and have excellent recyclability. . In particular, particle board is a wood board made by finely cutting wood (fine pieces) by applying an adhesive and heat-pressing it to a density of 0.5-0.9 g / cm ³ The feature is that it can be processed freely and there is little dimensional deviation and warpage.

The method for producing the fiber board of the present invention is as follows. 1. Mixing wood fiber and microcapsules 2. The step of mixing or spraying the adhesive, It consists of three steps of thermocompression bonding. 1. In the step (2), the fiber pieces cut into an appropriate size may be mixed with the powdered or granulated solid microcapsule solid material. Microcapsule solids are powdered and granulated from a microcapsule slurry to a size of about 1 mm to 10 cm in diameter using various dryers such as a drum dryer, a spray dryer, and a freeze dryer, and a granulator. Alternatively, a mixture of the fiber pieces and the microcapsule slurry that has been previously mixed and bound and granulated with a fluidized bed dryer may be used.

2. The adhesive used in the step of can be used with any of thermoplastic and thermosetting properties, but is preferably a phenol resin adhesive, a urea resin adhesive,
Water-resistant adhesives such as melamine resin-based adhesives, urea-melamine co-condensed resin-based adhesives, resorcinol-type adhesives, and polyurethane-based adhesives are used. These adhesives are either premixed with the fiber pieces or continuously sprinkled from above and mixed evenly. Furthermore, as a building material, mold proof,
Insect repellent and flame retardant agents may be added in this step. Furthermore, if necessary, anti-aging agents, antioxidants, plasticizers, tackifiers, lubricants, colorants, curing agents, foaming agents, synthetic fibers, synthetic resins, heat insulating materials, etc. may be added, injected, and laminated. It is possible.

The solid weight ratio of the fibers of the present invention to the microcapsules can be freely set, but the weight ratio of the microcapsules in the fiber board is 30% or more, preferably 50 to 90, so as to maximize the heat storage property. % Range is preferred. If it is more than this, the heat storage property is sufficient, but the strength of the fiber board decreases, which is not preferable. The heat storage amount of the fiber board is determined by the content ratio of the microcapsules, the weight per unit area of the fiber board itself, and the purpose. The amount of heat required for fusion depends on the materials that make up the building, the environment, the size, and the area, but the temperature rise inside the building during the daytime in summer and the apparent temperature rise or drop without using heating equipment in winter are suppressed. It is necessary to knead only microcapsules. Specifically, it is preferable to knead microcapsules containing a heat storage material having a melting point in the range of 5 to 50 ° C. into a fiber board so that the heat of fusion per 1 m ² is 60 kJ / m ² or more.

Generally, as a method of microencapsulating a heat storage material, an encapsulation method by a composite emulsion method (Japanese Patent Laid-Open No. 62-1452) and a method of spraying a thermoplastic resin on the surface of heat storage material particles (the same 62- No. 45680), a method of forming a thermoplastic resin in the liquid on the surface of the heat storage material particles (No. 62-149334), and a method of polymerizing and coating a monomer on the surface of the heat storage material particles (No. 62-22).
5241), a method for producing polyamide-coated microcapsules by an interfacial polycondensation reaction (Japanese Patent Laid-Open No. 2-258052), and the like.

As the capsule membrane material, polystyrene, polyacrylonitrile, polyamide, polyacrylamide, obtained by a method such as an interfacial polymerization method or an in situ method,
Ethyl cellulose, polyurethane, aminoplast resin, or synthetic or natural resin using coacervation method of gelatin and carboxymethyl cellulose or gum arabic is used, but it is thermally stable because it is pressed at high temperature in thermocompression bonding process. A microcapsule having a thermosetting resin film is preferable, and a microcapsule using a urea formalin resin or melamine formalin resin film by an in-situ method that can obtain a microcapsule of good quality even with an aliphatic hydrocarbon compound is particularly preferable.

The phase change point of the heat storage material used in the present invention, that is, the melting point, has a lower limit at which it is felt comfortable in the living temperature range,
It is preferable to set in a temperature range including a heat storage temperature range such as floor heating, and it is preferable to set in a range of 5 to 50 ° C. Specifically, n-paraffins having about 14 to 30 carbon atoms, inorganic eutectic and inorganic hydrates, fatty acids such as palmitic acid and myristic acid, and aromatics such as benzene and p-xylene. Group hydrocarbon compounds, ester compounds such as isopropyl palmitate and butyl stearate, and compounds such as alcohols such as stearyl alcohol,
A chemically and physically stable and inexpensive material is used. These may be used as a mixture, and if necessary, a supercooling preventing material, a specific gravity adjusting material, a deterioration preventing agent and the like may be added. It is also possible to mix and use two or more types of microcapsules having different melting points.

The particle size of the microcapsules according to the present invention is preferably 10 μm or less, particularly preferably 5 μm or less in order to prevent destruction due to physical pressure during the coating or impregnation process. The particle size of the microcapsules depends on the type and concentration of the emulsifier, the temperature of the emulsion during emulsification, the emulsification ratio (volume ratio of the water phase and the oil phase), the operating conditions of the atomizer called an emulsifier, disperser, etc. (Agitation rotation speed, time, etc.) are appropriately adjusted to set a desired particle size. When the particle size is more than this range, the microcapsules are easily broken by external pressure, and when the specific gravity of the heat storage material is largely different from that of the dispersion medium, the microcapsules easily float or settle, which is not preferable.

3. The thermocompression bonding step is a step of imparting strength to the aggregate of fiber pieces, and the density of the fiber board changes with pressure. Specifically, the surface pressure is 10 to 100 kg / m ²
The pressure and temperature are within the range of 80 to 160 ° C. for 1 minute or more. A pressure or temperature higher than this range is not preferable because it causes deterioration of the microcapsules, and a pressure or temperature lower than this range is not preferable because the strength as a board is not expressed.

The fiber board of the present invention can be used as a building material having a heat storage property by being attached to the underfloor or the ceiling of a house or building. In addition, since it also has an effect of being excellent in soundproofing, a house having a plurality of households such as a second-generation house or an apartment house has an advantage of absorbing noise and vibration that cause complaints.
It is also possible to cut or make a hole in the same manner as the construction board, and to paste wallpaper on the board. The heat storage board of the present invention is made of glass wool,
It is a preferred embodiment because a synergistic effect of heat insulation and heat storage can be obtained by using it in combination with a heat insulation material such as hollow particles, urethane foam, and foaming resin.

[0017]

EXAMPLES Examples of the present invention will be shown below. The numbers of parts in the examples represent solid parts by mass. Further, the melting point and the heat of fusion are measured by a differential calorimeter (DSC-7 type manufactured by Perkin Elmer, USA).
Was measured using.

Example To 12 parts by weight of melamine powder, 15.4 parts by weight of 37% aqueous formaldehyde solution and 40 parts by weight of water were added to adjust pH to 8, and then heated to about 70 ° C. to prepare an aqueous solution of melamine-formaldehyde initial condensate. Got 80 parts by weight of n-octadecane (melting point 26-28 ° C) was vigorously stirred as a heat storage material in 100 parts by weight of an aqueous solution of sodium salt of 10% styrene-maleic anhydride copolymer adjusted to pH 4.5. It was added and emulsified until the particle diameter became 3.0 μm.

To the obtained emulsion, the whole amount of the above melamine-formaldehyde initial condensate aqueous solution was added and stirred at 70 ° C. for 2 hours, after which the pH was raised to 9 and water was added to obtain a dry solids concentration of 40%. A heat storage material microcapsule dispersion liquid of was obtained. This microcapsule dispersion was dried with a spray dryer to a water content of 3% or less to obtain a microcapsule powder having a particle size of about 30 μm. 100 parts of this microcapsule powder and 100 parts of a strand-shaped cedar material chip as a board material were thoroughly mixed, and 20 parts of a powdery urea resin adhesive was added to obtain a particle board.

The structure of the board is three layers, the two layers on the front and back sides are made of cedar wood for maintaining strength, and the core layer is made of a mixture of cedar wood chips and expanded polystyrene foam for weight reduction. . Immediately after microwave heating, thermocompression bonding was performed by hot pressing for 5 minutes under the conditions of 140 ° C. and 20 kg / cm ² , the foam and the adhesive were melted and then solidified by cold pressing to obtain a board having a thickness of 12 mm.

A commercially available wallpaper was attached to the surface of this fiber board, and a urethane foam sheet was attached to the back surface as a heat insulating material to obtain a heat storage fiber board having a thickness of 15 mm. This fiber board was combined to produce a cubic wooden box with a side of 50 cm. The temperature of the center of the wooden box was measured by repeating the temperature increase and decrease of the outside temperature of the wooden box between 0 and 40 ° C for 1 hour in an atmosphere in which the environmental temperature of the wooden box can be forcibly controlled. It was found that in the wooden box, an environment in which the temperature change width is small in the range of 22 to 28 ° C and the temperature range of around 27 ° C is maintained for a long time can be obtained. The fiberboard produced in exactly the same manner as in the example without the microcapsules did not show any temperature-sustaining effect.

[0022]

As is clear from the results of the examples, the heat-retaining fiber board of the present invention has the same shape and properties as those of ordinary particle boards and fiber boards but has heat-retaining property. Therefore, by using it as an interior material of a house or a building, it becomes possible to store a large amount of heat or cold, which greatly contributes to the saving of energy required for heating and cooling and the effective use of solar energy. Also, by using it as a floor material, it is possible to obtain a secondary effect that is very convenient as an apartment house that is excellent in soundproofing and sound absorbing properties.

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Claims (3)

[Claims] 1. A heat storage fiber board obtained by thermocompression molding a composition comprising a microcapsule containing a heat storage material, wood fiber, and an adhesive. 2. The microcapsule film is a thermosetting urea formalin resin or melamine formalin resin film and has a volume average particle size of 10 μm or less.
The heat storage fiber board described. 3. A method of using the heat storage fiber board as an interior material for construction, comprising microcapsules containing a heat storage material having a melting point in the range of 5 to 50 ° C.